+++ /dev/null
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
-/***
- This file is part of systemd.
-
- Copyright 2010 ProFUSION embedded systems
-
- systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as published by
- the Free Software Foundation; either version 2.1 of the License, or
- (at your option) any later version.
-
- systemd 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
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
-***/
-
-#include <errno.h>
-#include <fcntl.h>
-#include <string.h>
-#include <sys/mount.h>
-#include <sys/swap.h>
-#include <linux/loop.h>
-#include <linux/dm-ioctl.h>
-
-#include "list.h"
-#include "mount-setup.h"
-#include "umount.h"
-#include "path-util.h"
-#include "util.h"
-#include "virt.h"
-#include "libudev.h"
-#include "udev-util.h"
-
-typedef struct MountPoint {
- char *path;
- dev_t devnum;
- LIST_FIELDS(struct MountPoint, mount_point);
-} MountPoint;
-
-static void mount_point_free(MountPoint **head, MountPoint *m) {
- assert(head);
- assert(m);
-
- LIST_REMOVE(mount_point, *head, m);
-
- free(m->path);
- free(m);
-}
-
-static void mount_points_list_free(MountPoint **head) {
- assert(head);
-
- while (*head)
- mount_point_free(head, *head);
-}
-
-static int mount_points_list_get(MountPoint **head) {
- _cleanup_fclose_ FILE *proc_self_mountinfo = NULL;
- unsigned int i;
-
- assert(head);
-
- proc_self_mountinfo = fopen("/proc/self/mountinfo", "re");
- if (!proc_self_mountinfo)
- return -errno;
-
- for (i = 1;; i++) {
- _cleanup_free_ char *path = NULL;
- char *p = NULL;
- MountPoint *m;
- int k;
-
- k = fscanf(proc_self_mountinfo,
- "%*s " /* (1) mount id */
- "%*s " /* (2) parent id */
- "%*s " /* (3) major:minor */
- "%*s " /* (4) root */
- "%ms " /* (5) mount point */
- "%*s" /* (6) mount options */
- "%*[^-]" /* (7) optional fields */
- "- " /* (8) separator */
- "%*s " /* (9) file system type */
- "%*s" /* (10) mount source */
- "%*s" /* (11) mount options 2 */
- "%*[^\n]", /* some rubbish at the end */
- &path);
- if (k != 1) {
- if (k == EOF)
- break;
-
- log_warning("Failed to parse /proc/self/mountinfo:%u.", i);
- continue;
- }
-
- p = cunescape(path);
- if (!p)
- return -ENOMEM;
-
- /* Ignore mount points we can't unmount because they
- * are API or because we are keeping them open (like
- * /dev/console). Also, ignore all mounts below API
- * file systems, since they are likely virtual too,
- * and hence not worth spending time on. Also, in
- * unprivileged containers we might lack the rights to
- * unmount these things, hence don't bother. */
- if (mount_point_is_api(p) ||
- mount_point_ignore(p) ||
- path_startswith(p, "/dev") ||
- path_startswith(p, "/sys") ||
- path_startswith(p, "/proc")) {
- free(p);
- continue;
- }
-
- m = new0(MountPoint, 1);
- if (!m) {
- free(p);
- return -ENOMEM;
- }
-
- m->path = p;
- LIST_PREPEND(mount_point, *head, m);
- }
-
- return 0;
-}
-
-static int swap_list_get(MountPoint **head) {
- _cleanup_fclose_ FILE *proc_swaps = NULL;
- unsigned int i;
-
- assert(head);
-
- if (!(proc_swaps = fopen("/proc/swaps", "re")))
- return (errno == ENOENT) ? 0 : -errno;
-
- (void) fscanf(proc_swaps, "%*s %*s %*s %*s %*s\n");
-
- for (i = 2;; i++) {
- MountPoint *swap;
- char *dev = NULL, *d;
- int k;
-
- if ((k = fscanf(proc_swaps,
- "%ms " /* device/file */
- "%*s " /* type of swap */
- "%*s " /* swap size */
- "%*s " /* used */
- "%*s\n", /* priority */
- &dev)) != 1) {
-
- if (k == EOF)
- break;
-
- log_warning("Failed to parse /proc/swaps:%u.", i);
-
- free(dev);
- continue;
- }
-
- if (endswith(dev, " (deleted)")) {
- free(dev);
- continue;
- }
-
- d = cunescape(dev);
- free(dev);
-
- if (!d) {
- return -ENOMEM;
- }
-
- if (!(swap = new0(MountPoint, 1))) {
- free(d);
- return -ENOMEM;
- }
-
- swap->path = d;
- LIST_PREPEND(mount_point, *head, swap);
- }
-
- return 0;
-}
-
-static int loopback_list_get(MountPoint **head) {
- _cleanup_udev_enumerate_unref_ struct udev_enumerate *e = NULL;
- struct udev_list_entry *item = NULL, *first = NULL;
- _cleanup_udev_unref_ struct udev *udev = NULL;
- int r;
-
- assert(head);
-
- udev = udev_new();
- if (!udev)
- return -ENOMEM;
-
- e = udev_enumerate_new(udev);
- if (!e)
- return -ENOMEM;
-
- r = udev_enumerate_add_match_subsystem(e, "block");
- if (r < 0)
- return r;
-
- r = udev_enumerate_add_match_sysname(e, "loop*");
- if (r < 0)
- return r;
-
- r = udev_enumerate_add_match_sysattr(e, "loop/backing_file", NULL);
- if (r < 0)
- return r;
-
- r = udev_enumerate_scan_devices(e);
- if (r < 0)
- return r;
-
- first = udev_enumerate_get_list_entry(e);
- udev_list_entry_foreach(item, first) {
- MountPoint *lb;
- _cleanup_udev_device_unref_ struct udev_device *d;
- char *loop;
- const char *dn;
-
- d = udev_device_new_from_syspath(udev, udev_list_entry_get_name(item));
- if (!d)
- return -ENOMEM;
-
- dn = udev_device_get_devnode(d);
- if (!dn)
- continue;
-
- loop = strdup(dn);
- if (!loop)
- return -ENOMEM;
-
- lb = new0(MountPoint, 1);
- if (!lb) {
- free(loop);
- return -ENOMEM;
- }
-
- lb->path = loop;
- LIST_PREPEND(mount_point, *head, lb);
- }
-
- return 0;
-}
-
-static int dm_list_get(MountPoint **head) {
- _cleanup_udev_enumerate_unref_ struct udev_enumerate *e = NULL;
- struct udev_list_entry *item = NULL, *first = NULL;
- _cleanup_udev_unref_ struct udev *udev = NULL;
- int r;
-
- assert(head);
-
- udev = udev_new();
- if (!udev)
- return -ENOMEM;
-
- e = udev_enumerate_new(udev);
- if (!e)
- return -ENOMEM;
-
- r = udev_enumerate_add_match_subsystem(e, "block");
- if (r < 0)
- return r;
-
- r = udev_enumerate_add_match_sysname(e, "dm-*");
- if (r < 0)
- return r;
-
- r = udev_enumerate_scan_devices(e);
- if (r < 0)
- return r;
-
- first = udev_enumerate_get_list_entry(e);
- udev_list_entry_foreach(item, first) {
- MountPoint *m;
- _cleanup_udev_device_unref_ struct udev_device *d;
- dev_t devnum;
- char *node;
- const char *dn;
-
- d = udev_device_new_from_syspath(udev, udev_list_entry_get_name(item));
- if (!d)
- return -ENOMEM;
-
- devnum = udev_device_get_devnum(d);
- dn = udev_device_get_devnode(d);
- if (major(devnum) == 0 || !dn)
- continue;
-
- node = strdup(dn);
- if (!node)
- return -ENOMEM;
-
- m = new(MountPoint, 1);
- if (!m) {
- free(node);
- return -ENOMEM;
- }
-
- m->path = node;
- m->devnum = devnum;
- LIST_PREPEND(mount_point, *head, m);
- }
-
- return 0;
-}
-
-static int delete_loopback(const char *device) {
- _cleanup_close_ int fd = -1;
- int r;
-
- fd = open(device, O_RDONLY|O_CLOEXEC);
- if (fd < 0)
- return errno == ENOENT ? 0 : -errno;
-
- r = ioctl(fd, LOOP_CLR_FD, 0);
- if (r >= 0)
- return 1;
-
- /* ENXIO: not bound, so no error */
- if (errno == ENXIO)
- return 0;
-
- return -errno;
-}
-
-static int delete_dm(dev_t devnum) {
- _cleanup_close_ int fd = -1;
- int r;
- struct dm_ioctl dm = {
- .version = {DM_VERSION_MAJOR,
- DM_VERSION_MINOR,
- DM_VERSION_PATCHLEVEL},
- .data_size = sizeof(dm),
- .dev = devnum,
- };
-
- assert(major(devnum) != 0);
-
- fd = open("/dev/mapper/control", O_RDWR|O_CLOEXEC);
- if (fd < 0)
- return -errno;
-
- r = ioctl(fd, DM_DEV_REMOVE, &dm);
- return r >= 0 ? 0 : -errno;
-}
-
-static int mount_points_list_umount(MountPoint **head, bool *changed, bool log_error) {
- MountPoint *m, *n;
- int n_failed = 0;
-
- assert(head);
-
- LIST_FOREACH_SAFE(mount_point, m, n, *head) {
-
- /* If we are in a container, don't attempt to
- read-only mount anything as that brings no real
- benefits, but might confuse the host, as we remount
- the superblock here, not the bind mound. */
- if (detect_container(NULL) <= 0) {
- /* We always try to remount directories
- * read-only first, before we go on and umount
- * them.
- *
- * Mount points can be stacked. If a mount
- * point is stacked below / or /usr, we
- * cannot umount or remount it directly,
- * since there is no way to refer to the
- * underlying mount. There's nothing we can do
- * about it for the general case, but we can
- * do something about it if it is aliased
- * somehwere else via a bind mount. If we
- * explicitly remount the super block of that
- * alias read-only we hence should be
- * relatively safe regarding keeping the fs we
- * can otherwise not see dirty. */
- mount(NULL, m->path, NULL, MS_REMOUNT|MS_RDONLY, NULL);
- }
-
- /* Skip / and /usr since we cannot unmount that
- * anyway, since we are running from it. They have
- * already been remounted ro. */
- if (path_equal(m->path, "/")
-#ifndef HAVE_SPLIT_USR
- || path_equal(m->path, "/usr")
-#endif
- )
- continue;
-
- /* Trying to umount. We don't force here since we rely
- * on busy NFS and FUSE file systems to return EBUSY
- * until we closed everything on top of them. */
- log_info("Unmounting %s.", m->path);
- if (umount2(m->path, 0) == 0) {
- if (changed)
- *changed = true;
-
- mount_point_free(head, m);
- } else if (log_error) {
- log_warning_errno(errno, "Could not unmount %s: %m", m->path);
- n_failed++;
- }
- }
-
- return n_failed;
-}
-
-static int swap_points_list_off(MountPoint **head, bool *changed) {
- MountPoint *m, *n;
- int n_failed = 0;
-
- assert(head);
-
- LIST_FOREACH_SAFE(mount_point, m, n, *head) {
- log_info("Deactivating swap %s.", m->path);
- if (swapoff(m->path) == 0) {
- if (changed)
- *changed = true;
-
- mount_point_free(head, m);
- } else {
- log_warning_errno(errno, "Could not deactivate swap %s: %m", m->path);
- n_failed++;
- }
- }
-
- return n_failed;
-}
-
-static int loopback_points_list_detach(MountPoint **head, bool *changed) {
- MountPoint *m, *n;
- int n_failed = 0, k;
- struct stat root_st;
-
- assert(head);
-
- k = lstat("/", &root_st);
-
- LIST_FOREACH_SAFE(mount_point, m, n, *head) {
- int r;
- struct stat loopback_st;
-
- if (k >= 0 &&
- major(root_st.st_dev) != 0 &&
- lstat(m->path, &loopback_st) >= 0 &&
- root_st.st_dev == loopback_st.st_rdev) {
- n_failed ++;
- continue;
- }
-
- log_info("Detaching loopback %s.", m->path);
- r = delete_loopback(m->path);
- if (r >= 0) {
- if (r > 0 && changed)
- *changed = true;
-
- mount_point_free(head, m);
- } else {
- log_warning_errno(errno, "Could not detach loopback %s: %m", m->path);
- n_failed++;
- }
- }
-
- return n_failed;
-}
-
-static int dm_points_list_detach(MountPoint **head, bool *changed) {
- MountPoint *m, *n;
- int n_failed = 0, k;
- struct stat root_st;
-
- assert(head);
-
- k = lstat("/", &root_st);
-
- LIST_FOREACH_SAFE(mount_point, m, n, *head) {
- int r;
-
- if (k >= 0 &&
- major(root_st.st_dev) != 0 &&
- root_st.st_dev == m->devnum) {
- n_failed ++;
- continue;
- }
-
- log_info("Detaching DM %u:%u.", major(m->devnum), minor(m->devnum));
- r = delete_dm(m->devnum);
- if (r >= 0) {
- if (changed)
- *changed = true;
-
- mount_point_free(head, m);
- } else {
- log_warning_errno(errno, "Could not detach DM %s: %m", m->path);
- n_failed++;
- }
- }
-
- return n_failed;
-}
-
-int umount_all(bool *changed) {
- int r;
- bool umount_changed;
- LIST_HEAD(MountPoint, mp_list_head);
-
- LIST_HEAD_INIT(mp_list_head);
- r = mount_points_list_get(&mp_list_head);
- if (r < 0)
- goto end;
-
- /* retry umount, until nothing can be umounted anymore */
- do {
- umount_changed = false;
-
- mount_points_list_umount(&mp_list_head, &umount_changed, false);
- if (umount_changed)
- *changed = true;
-
- } while (umount_changed);
-
- /* umount one more time with logging enabled */
- r = mount_points_list_umount(&mp_list_head, &umount_changed, true);
- if (r <= 0)
- goto end;
-
- end:
- mount_points_list_free(&mp_list_head);
-
- return r;
-}
-
-int swapoff_all(bool *changed) {
- int r;
- LIST_HEAD(MountPoint, swap_list_head);
-
- LIST_HEAD_INIT(swap_list_head);
-
- r = swap_list_get(&swap_list_head);
- if (r < 0)
- goto end;
-
- r = swap_points_list_off(&swap_list_head, changed);
-
- end:
- mount_points_list_free(&swap_list_head);
-
- return r;
-}
-
-int loopback_detach_all(bool *changed) {
- int r;
- LIST_HEAD(MountPoint, loopback_list_head);
-
- LIST_HEAD_INIT(loopback_list_head);
-
- r = loopback_list_get(&loopback_list_head);
- if (r < 0)
- goto end;
-
- r = loopback_points_list_detach(&loopback_list_head, changed);
-
- end:
- mount_points_list_free(&loopback_list_head);
-
- return r;
-}
-
-int dm_detach_all(bool *changed) {
- int r;
- LIST_HEAD(MountPoint, dm_list_head);
-
- LIST_HEAD_INIT(dm_list_head);
-
- r = dm_list_get(&dm_list_head);
- if (r < 0)
- goto end;
-
- r = dm_points_list_detach(&dm_list_head, changed);
-
- end:
- mount_points_list_free(&dm_list_head);
-
- return r;
-}
~ianmdlvl / elogind.git / blobdiff