user-sessions: rely on PID 1 to kill sessions

As we want to centralized cgroup access we should stop killing the user
sessions directly from the systemd-user-sessions service. Instead, rely
on PID 1 doing this by adding the right ordering dependencies to the
session scope units.

1 files changed, 1 insertions, 110 deletions

diff --git a/src/login/user-sessions.c b/src/login/user-sessions.c
index 18066ccc39..45fb427671 100644
--- a/src/login/user-sessions.c
+++ b/src/login/user-sessions.c
@@ -25,109 +25,8 @@
 
 #include "log.h"
 #include "util.h"
-#include "cgroup-util.h"
 #include "fileio.h"
 
-static int kill_all_users(void) {
-        _cleanup_closedir_ DIR *d = NULL;
-        struct dirent *de;
-        int r = 0;
-
-        d = opendir("/run/systemd/users");
-        if (!d) {
-                if (errno == ENOENT)
-                        return 0;
-
-                log_error("Failed to open /run/systemd/users: %m");
-                return -errno;
-        }
-
-        FOREACH_DIRENT(de, d, return -errno) {
-                _cleanup_free_ char *cgroup = NULL;
-                char *a;
-                int k;
-
-                if (!dirent_is_file(de))
-                        continue;
-
-                a = strappenda("/run/systemd/users/", de->d_name);
-
-                k = parse_env_file(a, NEWLINE, "CGROUP", &cgroup, NULL);
-                if (k < 0) {
-                        if (k != -ENOENT) {
-                                log_error("Failed to read user data: %s", strerror(-k));
-                                r = k;
-                        }
-
-                        continue;
-                }
-
-                if (!cgroup) {
-                        log_error("User data did not contain cgroup field.");
-                        r = -ENOENT;
-                        continue;
-                }
-
-                k = cg_kill_recursive_and_wait(SYSTEMD_CGROUP_CONTROLLER, cgroup, true);
-                if (k < 0) {
-                        log_error("Failed to kill cgroup %s: %s", cgroup, strerror(-k));
-                        r = k;
-                }
-        }
-
-        return r;
-}
-
-static int kill_all_sessions(void) {
-        _cleanup_closedir_ DIR *d = NULL;
-        struct dirent *de;
-        int r = 0;
-
-        d = opendir("/run/systemd/sessions");
-        if (!d) {
-                if (errno == ENOENT)
-                        return 0;
-
-                log_error("Failed to open /run/systemd/sessions: %m");
-                return -errno;
-        }
-
-        FOREACH_DIRENT(de, d, return -errno) {
-                _cleanup_free_ char *cgroup = NULL;
-                char *a;
-                int k;
-
-                if (!dirent_is_file(de))
-                        continue;
-
-                a = strappenda("/run/systemd/sessions/", de->d_name);
-
-                k = parse_env_file(a, NEWLINE, "CGROUP", &cgroup, NULL);
-                if (k < 0) {
-                        if (k != -ENOENT) {
-                                log_error("Failed to read session data: %s", strerror(-k));
-                                r = k;
-                        }
-
-                        continue;
-                }
-
-                if (!cgroup) {
-                        log_error("Session data did not contain cgroup field.");
-                        r = -ENOENT;
-                        continue;
-                }
-
-                k = cg_kill_recursive_and_wait(SYSTEMD_CGROUP_CONTROLLER, cgroup, true);
-                if (k < 0) {
-                        log_error("Failed to kill cgroup %s: %s", cgroup, strerror(-k));
-                        r = k;
-                }
-        }
-
-        return r;
-}
-
 int main(int argc, char*argv[]) {
         int ret = EXIT_FAILURE;
 
@@ -167,20 +66,12 @@ int main(int argc, char*argv[]) {
                         goto finish;
 
         } else if (streq(argv[1], "stop")) {
-                int r, q;
+                int r;
 
                 r = write_string_file_atomic("/run/nologin", "System is going down.");
                 if (r < 0)
                         log_error("Failed to create /run/nologin: %s", strerror(-r));
 
-                q = kill_all_users();
-                if (q < 0 && r >= 0)
-                        r = q;
-
-                q = kill_all_sessions();
-                if (q < 0 && r >= 0)
-                        r = q;
-
         } else {
                 log_error("Unknown verb %s.", argv[1]);
                 goto finish;