umount: try to get rid of DM devices

3 files changed, 164 insertions, 12 deletions

diff --git a/src/shutdown.c b/src/shutdown.c
index be3fff41c..2c14371df 100644
--- a/src/shutdown.c
+++ b/src/shutdown.c
@@ -200,7 +200,7 @@ finish:
 
 int main(int argc, char *argv[]) {
         int cmd, r, retries;
-        bool need_umount = true, need_swapoff = true, need_loop_detach = true;
+        bool need_umount = true, need_swapoff = true, need_loop_detach = true, need_dm_detach = true;
 
         log_parse_environment();
         log_set_target(LOG_TARGET_CONSOLE); /* syslog will die if not gone yet */
@@ -248,7 +248,7 @@ int main(int argc, char *argv[]) {
 
         /* Unmount all mountpoints, swaps, and loopback devices */
         retries = FINALIZE_ATTEMPTS;
-        while (need_umount || need_swapoff || need_loop_detach) {
+        for (;;) {
                 if (need_umount) {
                         log_info("Unmounting filesystems.");
                         r = umount_all();
@@ -280,10 +280,20 @@ int main(int argc, char *argv[]) {
                                 log_warning("Not all loop devices detached, %d left.", r);
                         else
                                 log_error("Error detaching loop devices: %s", strerror(-r));
+                }
 
+                if (need_dm_detach) {
+                        log_info("Detaching DM devices.");
+                        r = dm_detach_all();
+                        if (r == 0)
+                                need_dm_detach = false;
+                        else if (r > 0)
+                                log_warning("Not all dm devices detached, %d left.", r);
+                        else
+                                log_error("Error detaching dm devices: %s", strerror(-r));
                 }
 
-                if (need_umount || need_swapoff || need_loop_detach) {
+                if (need_umount || need_swapoff || need_loop_detach || need_dm_detach) {
                         retries--;
 
                         if (retries == FINALIZE_CRITICAL_ATTEMPTS) {
@@ -295,11 +305,12 @@ int main(int argc, char *argv[]) {
                         if (retries > 0)
                                 log_info("Action still required, %d tries left.", retries);
                         else {
-                                log_error("Giving up. Actions left: Umount=%s, Swap off=%s, Loop detach=%s",
-                                          yes_no(need_umount), yes_no(need_swapoff), yes_no(need_loop_detach));
+                                log_error("Giving up. Actions left: Umount=%s, Swap off=%s, Loop detach=%s, dm detach=%s",
+                                          yes_no(need_umount), yes_no(need_swapoff), yes_no(need_loop_detach), yes_no(need_dm_detach));
                                 break;
                         }
-                }
+                } else
+                        break;
         }
 
         sync();
diff --git a/src/umount.c b/src/umount.c
index 44bed611e..28cfd7e7c 100644
--- a/src/umount.c
+++ b/src/umount.c
@@ -26,6 +26,7 @@
 #include <sys/swap.h>
 #include <unistd.h>
 #include <linux/loop.h>
+#include <linux/dm-ioctl.h>
 #include <libudev.h>
 
 #include "list.h"
@@ -208,12 +209,8 @@ static int loopback_list_get(MountPoint **loopback_list_head) {
                 goto finish;
         }
 
-        if (udev_enumerate_add_match_subsystem(e, "block") < 0) {
-                r = -EIO;
-                goto finish;
-        }
-
-        if (udev_enumerate_add_match_sysname(e, "loop*") < 0) {
+        if (udev_enumerate_add_match_subsystem(e, "block") < 0 ||
+            udev_enumerate_add_match_sysname(e, "loop*") < 0) {
                 r = -EIO;
                 goto finish;
         }
@@ -268,6 +265,87 @@ finish:
         return r;
 }
 
+static int dm_list_get(MountPoint **dm_list_head) {
+        int r;
+        struct udev *udev;
+        struct udev_enumerate *e = NULL;
+        struct udev_list_entry *item = NULL, *first = NULL;
+
+        if (!(udev = udev_new())) {
+                r = -ENOMEM;
+                goto finish;
+        }
+
+        if (!(e = udev_enumerate_new(udev))) {
+                r = -ENOMEM;
+                goto finish;
+        }
+
+        if (udev_enumerate_add_match_subsystem(e, "block") < 0 ||
+            udev_enumerate_add_match_sysname(e, "dm-*") < 0) {
+                r = -EIO;
+                goto finish;
+        }
+
+        if (udev_enumerate_scan_devices(e) < 0) {
+                r = -EIO;
+                goto finish;
+        }
+
+        first = udev_enumerate_get_list_entry(e);
+
+        udev_list_entry_foreach(item, first) {
+                MountPoint *lb;
+                struct udev_device *d;
+                char *dm = NULL;
+                struct udev_list_entry *dlink = NULL, *first_dlink = NULL;
+
+                if (!(d = udev_device_new_from_syspath(udev, udev_list_entry_get_name(item)))) {
+                        r = -ENOMEM;
+                        goto finish;
+                }
+
+                first_dlink = udev_device_get_devlinks_list_entry(d);
+                udev_list_entry_foreach(dlink, first_dlink) {
+
+                        if (startswith(udev_list_entry_get_name(dlink), "/dev/mapper/")) {
+
+                                if (!(dm = strdup(udev_list_entry_get_name(dlink)))) {
+                                        udev_device_unref(d);
+                                        r = -ENOMEM;
+                                        goto finish;
+                                }
+
+                                break;
+                        }
+                }
+
+                udev_device_unref(d);
+
+                if (!dm)
+                        continue;
+
+                if (!(lb = mount_point_alloc(dm))) {
+                        free(dm);
+                        r = -ENOMEM;
+                        goto finish;
+                }
+
+                LIST_PREPEND(MountPoint, mount_point, *dm_list_head, lb);
+        }
+
+        r = 0;
+
+finish:
+        if (e)
+                udev_enumerate_unref(e);
+
+        if (udev)
+                udev_unref(udev);
+
+        return r;
+}
+
 static int delete_loopback(const char *device) {
         int fd, r;
 
@@ -281,6 +359,33 @@ static int delete_loopback(const char *device) {
         return (r >= 0 || errno == ENXIO) ? 0 : -errno;
 }
 
+static int delete_dm(const char *device) {
+        int fd, r;
+        struct dm_ioctl dm;
+
+        assert(device);
+
+        if (!startswith(device, "/dev/mapper/"))
+                return -EIO;
+
+        if ((fd = open("/dev/mapper/control", O_RDWR|O_CLOEXEC)) < 0)
+                return -errno;
+
+        zero(dm);
+        dm.version[0] = DM_VERSION_MAJOR;
+        dm.version[1] = DM_VERSION_MINOR;
+        dm.version[2] = DM_VERSION_PATCHLEVEL;
+
+        dm.data_size = sizeof(dm);
+
+        strncpy(dm.name, device + 12, sizeof(dm.name));
+
+        r = ioctl(fd, DM_DEV_REMOVE, &dm);
+        close_nointr_nofail(fd);
+
+        return r >= 0 ? 0 : -errno;
+}
+
 static int mount_points_list_umount(MountPoint **mount_point_list_head) {
         MountPoint *mp, *mp_next;
         int failed = 0;
@@ -350,6 +455,22 @@ static int loopback_points_list_detach(MountPoint **loopback_list_head) {
         return failed;
 }
 
+static int dm_points_list_detach(MountPoint **dm_list_head) {
+        MountPoint *dm, *dm_next;
+        int failed = 0;
+
+        LIST_FOREACH_SAFE(mount_point, dm, dm_next, *dm_list_head) {
+                if (delete_dm(dm->path) == 0)
+                        mount_point_remove_and_free(dm, dm_list_head);
+                else {
+                        log_warning("Could not delete dm %s: %m", dm->path);
+                        failed++;
+                }
+        }
+
+        return failed;
+}
+
 int umount_all(void) {
         int r;
         LIST_HEAD(MountPoint, mp_list_head);
@@ -407,3 +528,21 @@ int loopback_detach_all(void) {
 
         return r;
 }
+
+int dm_detach_all(void) {
+        int r;
+        LIST_HEAD(MountPoint, dm_list_head);
+
+        LIST_HEAD_INIT(MountPoint, dm_list_head);
+
+        r = dm_list_get(&dm_list_head);
+        if (r < 0)
+                goto end;
+
+        r = dm_points_list_detach(&dm_list_head);
+
+  end:
+        mount_points_list_free(&dm_list_head);
+
+        return r;
+}
diff --git a/src/umount.h b/src/umount.h
index aeccc00f1..c06ca867a 100644
--- a/src/umount.h
+++ b/src/umount.h
@@ -28,4 +28,6 @@ int swapoff_all(void);
 
 int loopback_detach_all(void);
 
+int dm_detach_all(void);
+
 #endif