X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fumount.c;h=4e036d82a30555988c18fea2c4dc8a8333f4b78c;hp=6fe0a26dd413278ae704e1037b0466abcdc04429;hb=cd0504d0a13d8297b97c9238fd1b94b4141c5aa8;hpb=c4f8bd1aef96063ccc2121fe2429a933a0b2068d

diff --git a/src/umount.c b/src/umount.c
index 6fe0a26dd..4e036d82a 100644
--- a/src/umount.c
+++ b/src/umount.c
@@ -37,6 +37,7 @@
 typedef struct MountPoint {
         char *path;
         dev_t devnum;
+        bool skip_ro;
         LIST_FIELDS (struct MountPoint, mount_point);
 } MountPoint;
 
@@ -71,6 +72,8 @@ static int mount_points_list_get(MountPoint **head) {
         for (i = 1;; i++) {
                 int k;
                 MountPoint *m;
+                char *root;
+                bool skip_ro;
 
                 path = p = NULL;
 
@@ -78,7 +81,7 @@ static int mount_points_list_get(MountPoint **head) {
                                 "%*s "       /* (1) mount id */
                                 "%*s "       /* (2) parent id */
                                 "%*s "       /* (3) major:minor */
-                                "%*s "       /* (4) root */
+                                "%ms "       /* (4) root */
                                 "%ms "       /* (5) mount point */
                                 "%*s"        /* (6) mount options */
                                 "%*[^-]"     /* (7) optional fields */
@@ -87,7 +90,8 @@ static int mount_points_list_get(MountPoint **head) {
                                 "%*s"        /* (10) mount source */
                                 "%*s"        /* (11) mount options 2 */
                                 "%*[^\n]",   /* some rubbish at the end */
-                                &path)) != 1) {
+                                &root,
+                                &path)) != 2) {
                         if (k == EOF)
                                 break;
 
@@ -97,6 +101,11 @@ static int mount_points_list_get(MountPoint **head) {
                         continue;
                 }
 
+                /* If we encounter a bind mount, don't try to remount
+                 * the source dir too early */
+                skip_ro = !streq(root, "/");
+                free(root);
+
                 p = cunescape(path);
                 free(path);
 
@@ -117,6 +126,7 @@ static int mount_points_list_get(MountPoint **head) {
                 }
 
                 m->path = p;
+                m->skip_ro = skip_ro;
                 LIST_PREPEND(MountPoint, mount_point, *head, m);
         }
 
@@ -136,7 +146,7 @@ static int swap_list_get(MountPoint **head) {
         assert(head);
 
         if (!(proc_swaps = fopen("/proc/swaps", "re")))
-                return -errno;
+                return (errno == ENOENT) ? 0 : -errno;
 
         (void) fscanf(proc_swaps, "%*s %*s %*s %*s %*s\n");
 
@@ -393,7 +403,7 @@ static int delete_dm(dev_t devnum) {
         return r >= 0 ? 0 : -errno;
 }
 
-static int mount_points_list_umount(MountPoint **head, bool *changed) {
+static int mount_points_list_umount(MountPoint **head, bool *changed, bool log_error) {
         MountPoint *m, *n;
         int n_failed = 0;
 
@@ -407,11 +417,12 @@ static int mount_points_list_umount(MountPoint **head, bool *changed) {
 
                 /* Trying to umount. Forcing to umount if busy (only for NFS mounts) */
                 if (umount2(m->path, MNT_FORCE) == 0) {
+                        log_info("Unmounted %s.", m->path);
                         if (changed)
                                 *changed = true;
 
                         mount_point_free(head, m);
-                } else {
+                } else if (log_error) {
                         log_warning("Could not unmount %s: %m", m->path);
                         n_failed++;
                 }
@@ -428,6 +439,11 @@ static int mount_points_list_remount_read_only(MountPoint **head, bool *changed)
 
         LIST_FOREACH_SAFE(mount_point, m, n, *head) {
 
+                if (m->skip_ro) {
+                        n_failed++;
+                        continue;
+                }
+
                 /* Trying to remount read-only */
                 if (mount(NULL, m->path, NULL, MS_MGC_VAL|MS_REMOUNT|MS_RDONLY, NULL) == 0) {
                         if (changed)
@@ -536,6 +552,8 @@ static int dm_points_list_detach(MountPoint **head, bool *changed) {
 
 int umount_all(bool *changed) {
         int r;
+        bool umount_changed;
+
         LIST_HEAD(MountPoint, mp_list_head);
 
         LIST_HEAD_INIT(MountPoint, mp_list_head);
@@ -544,7 +562,18 @@ int umount_all(bool *changed) {
         if (r < 0)
                 goto end;
 
-        r = mount_points_list_umount(&mp_list_head, changed);
+        /* 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;