chiark / gitweb /
core: expose a "Slice" property on Unit objects on the bus
[elogind.git] / src / core / dbus-unit.c
index 8433a720b2a6f41fc898fe855476dddc25fa53c7..b7391b5506d2945eed08e3ae1315d63311e15271 100644 (file)
 #include "bus-errors.h"
 #include "dbus-common.h"
 #include "selinux-access.h"
+#include "cgroup-util.h"
+#include "strv.h"
+#include "path-util.h"
+#include "fileio.h"
 
 const char bus_unit_interface[] _introspect_("Unit") = BUS_UNIT_INTERFACE;
 
@@ -77,6 +81,25 @@ static int bus_unit_append_following(DBusMessageIter *i, const char *property, v
         return 0;
 }
 
+static int bus_unit_append_slice(DBusMessageIter *i, const char *property, void *data) {
+        Unit *u = data;
+        const char *d;
+
+        assert(i);
+        assert(property);
+        assert(u);
+
+        if (UNIT_DEREF(u->slice))
+                d = UNIT_DEREF(u->slice)->id;
+        else
+                d = "";
+
+        if (!dbus_message_iter_append_basic(i, DBUS_TYPE_STRING, &d))
+                return -ENOMEM;
+
+        return 0;
+}
+
 static int bus_unit_append_dependencies(DBusMessageIter *i, const char *property, void *data) {
         Unit *u;
         Iterator j;
@@ -310,7 +333,7 @@ static int bus_unit_append_cgroups(DBusMessageIter *i, const char *property, voi
                 return -ENOMEM;
 
         LIST_FOREACH(by_unit, cgb, u->cgroup_bondings) {
-                char _cleanup_free_ *t = NULL;
+                _cleanup_free_ char *t = NULL;
                 bool success;
 
                 t = cgroup_bonding_to_string(cgb);
@@ -337,11 +360,11 @@ static int bus_unit_append_cgroup_attrs(DBusMessageIter *i, const char *property
                 return -ENOMEM;
 
         LIST_FOREACH(by_unit, a, u->cgroup_attributes) {
-                char _cleanup_free_ *v = NULL;
+                _cleanup_free_ char *v = NULL;
                 bool success;
 
-                if (a->map_callback)
-                        a->map_callback(a->controller, a->name, a->value, &v);
+                if (a->semantics && a->semantics->map_write)
+                        a->semantics->map_write(a->semantics, a->value, &v);
 
                 success =
                         dbus_message_iter_open_container(&sub, DBUS_TYPE_STRUCT, NULL, &sub2) &&
@@ -468,6 +491,90 @@ static DBusHandlerResult bus_unit_message_dispatch(Unit *u, DBusConnection *conn
                 if (!reply)
                         goto oom;
 
+        } else if (streq_ptr(dbus_message_get_member(message), "SetControlGroup")) {
+                DBusMessageIter iter;
+
+                SELINUX_UNIT_ACCESS_CHECK(u, connection, message, "start");
+
+                if (!dbus_message_iter_init(message, &iter))
+                        goto oom;
+
+                r = bus_unit_cgroup_set(u, &iter);
+                if (r < 0)
+                        return bus_send_error_reply(connection, message, NULL, r);
+
+                reply = dbus_message_new_method_return(message);
+                if (!reply)
+                        goto oom;
+
+        } else if (streq_ptr(dbus_message_get_member(message), "UnsetControlGroup")) {
+                DBusMessageIter iter;
+
+                SELINUX_UNIT_ACCESS_CHECK(u, connection, message, "stop");
+
+                if (!dbus_message_iter_init(message, &iter))
+                        goto oom;
+
+                r = bus_unit_cgroup_unset(u, &iter);
+                if (r < 0)
+                        return bus_send_error_reply(connection, message, NULL, r);
+
+                reply = dbus_message_new_method_return(message);
+                if (!reply)
+                        goto oom;
+        } else if (streq_ptr(dbus_message_get_member(message), "GetControlGroupAttribute")) {
+                DBusMessageIter iter;
+                _cleanup_strv_free_ char **list = NULL;
+
+                SELINUX_UNIT_ACCESS_CHECK(u, connection, message, "status");
+
+                if (!dbus_message_iter_init(message, &iter))
+                        goto oom;
+
+                r = bus_unit_cgroup_attribute_get(u, &iter, &list);
+                if (r < 0)
+                        return bus_send_error_reply(connection, message, NULL, r);
+
+                reply = dbus_message_new_method_return(message);
+                if (!reply)
+                        goto oom;
+
+                dbus_message_iter_init_append(reply, &iter);
+                if (bus_append_strv_iter(&iter, list) < 0)
+                        goto oom;
+
+        } else if (streq_ptr(dbus_message_get_member(message), "SetControlGroupAttribute")) {
+                DBusMessageIter iter;
+
+                SELINUX_UNIT_ACCESS_CHECK(u, connection, message, "start");
+
+                if (!dbus_message_iter_init(message, &iter))
+                        goto oom;
+
+                r = bus_unit_cgroup_attribute_set(u, &iter);
+                if (r < 0)
+                        return bus_send_error_reply(connection, message, NULL, r);
+
+                reply = dbus_message_new_method_return(message);
+                if (!reply)
+                        goto oom;
+
+        } else if (streq_ptr(dbus_message_get_member(message), "UnsetControlGroupAttribute")) {
+                DBusMessageIter iter;
+
+                SELINUX_UNIT_ACCESS_CHECK(u, connection, message, "stop");
+
+                if (!dbus_message_iter_init(message, &iter))
+                        goto oom;
+
+                r = bus_unit_cgroup_attribute_unset(u, &iter);
+                if (r < 0)
+                        return bus_send_error_reply(connection, message, NULL, r);
+
+                reply = dbus_message_new_method_return(message);
+                if (!reply)
+                        goto oom;
+
         } else if (UNIT_VTABLE(u)->bus_message_handler)
                 return UNIT_VTABLE(u)->bus_message_handler(u, connection, message);
         else
@@ -494,7 +601,7 @@ static DBusHandlerResult bus_unit_message_dispatch(Unit *u, DBusConnection *conn
         }
 
         if (reply)
-                if (!dbus_connection_send(connection, reply, NULL))
+                if (!bus_maybe_send_reply(connection, message, reply))
                         goto oom;
 
         return DBUS_HANDLER_RESULT_HANDLED;
@@ -585,7 +692,7 @@ static DBusHandlerResult bus_unit_message_handler(DBusConnection *connection, DB
 
                         free(introspection);
 
-                        if (!dbus_connection_send(connection, reply, NULL))
+                        if (!bus_maybe_send_reply(connection, message, reply))
                                 goto oom;
 
                         return DBUS_HANDLER_RESULT_HANDLED;
@@ -798,7 +905,7 @@ DBusHandlerResult bus_unit_queue_job(
                             DBUS_TYPE_INVALID))
                 goto oom;
 
-        if (!dbus_connection_send(connection, reply, NULL))
+        if (!bus_maybe_send_reply(connection, message, reply))
                 goto oom;
 
         return DBUS_HANDLER_RESULT_HANDLED;
@@ -809,10 +916,365 @@ oom:
         return DBUS_HANDLER_RESULT_NEED_MEMORY;
 }
 
+static int parse_mode(DBusMessageIter *iter, bool *runtime, bool next) {
+        const char *mode;
+        int r;
+
+        assert(iter);
+        assert(runtime);
+
+        r = bus_iter_get_basic_and_next(iter, DBUS_TYPE_STRING, &mode, next);
+        if (r < 0)
+                return r;
+
+        if (streq(mode, "runtime"))
+                *runtime = true;
+        else if (streq(mode, "persistent"))
+                *runtime = false;
+        else
+                return -EINVAL;
+
+        return 0;
+}
+
+int bus_unit_cgroup_set(Unit *u, DBusMessageIter *iter) {
+        _cleanup_free_ char *controller = NULL, *old_path = NULL, *new_path = NULL, *contents = NULL;
+        const char *name;
+        CGroupBonding *b;
+        bool runtime;
+        int r;
+
+        assert(u);
+        assert(iter);
+
+        if (!unit_get_exec_context(u))
+                return -EINVAL;
+
+        r = bus_iter_get_basic_and_next(iter, DBUS_TYPE_STRING, &name, true);
+        if (r < 0)
+                return r;
+
+        r = parse_mode(iter, &runtime, false);
+        if (r < 0)
+                return r;
+
+        r = cg_split_spec(name, &controller, &new_path);
+        if (r < 0)
+                return r;
+
+        if (!new_path) {
+                new_path = unit_default_cgroup_path(u);
+                if (!new_path)
+                        return -ENOMEM;
+        }
+
+        if (!controller || streq(controller, SYSTEMD_CGROUP_CONTROLLER))
+                return -EINVAL;
+
+        b = cgroup_bonding_find_list(u->cgroup_bondings, controller);
+        if (b) {
+                if (streq(b->path, new_path))
+                        return 0;
+
+                if (b->essential)
+                        return -EINVAL;
+
+                old_path = strdup(b->path);
+                if (!old_path)
+                        return -ENOMEM;
+        }
+
+        r = unit_add_cgroup_from_text(u, name, true, &b);
+        if (r < 0)
+                return r;
+        if (r > 0) {
+                CGroupAttribute *a;
+
+                /* Try to move things to the new place, and clean up the old place */
+                cgroup_bonding_realize(b);
+                cgroup_bonding_migrate(b, u->cgroup_bondings);
+
+                if (old_path)
+                        cg_trim(controller, old_path, true);
+
+                /* Apply the attributes to the new group */
+                LIST_FOREACH(by_unit, a, u->cgroup_attributes)
+                        if (streq(a->controller, controller))
+                                cgroup_attribute_apply(a, b);
+        }
+
+        contents = strjoin("[", UNIT_VTABLE(u)->exec_section, "]\n"
+                           "ControlGroup=", name, "\n", NULL);
+        if (!contents)
+                return -ENOMEM;
+
+        return unit_write_drop_in(u, runtime, controller, contents);
+}
+
+int bus_unit_cgroup_unset(Unit *u, DBusMessageIter *iter) {
+        _cleanup_free_ char *controller = NULL, *path = NULL, *target = NULL;
+        const char *name;
+        CGroupAttribute *a, *n;
+        CGroupBonding *b;
+        bool runtime;
+        int r;
+
+        assert(u);
+        assert(iter);
+
+        if (!unit_get_exec_context(u))
+                return -EINVAL;
+
+        r = bus_iter_get_basic_and_next(iter, DBUS_TYPE_STRING, &name, true);
+        if (r < 0)
+                return r;
+
+        r = parse_mode(iter, &runtime, false);
+        if (r < 0)
+                return r;
+
+        r = cg_split_spec(name, &controller, &path);
+        if (r < 0)
+                return r;
+
+        if (!controller || streq(controller, SYSTEMD_CGROUP_CONTROLLER))
+                return -EINVAL;
+
+        b = cgroup_bonding_find_list(u->cgroup_bondings, controller);
+        if (!b)
+                return -ENOENT;
+
+        if (path && !path_equal(path, b->path))
+                return -ENOENT;
+
+        if (b->essential)
+                return -EINVAL;
+
+        unit_remove_drop_in(u, runtime, controller);
+
+        /* Try to migrate the old group away */
+        if (cg_pid_get_path(controller, 0, &target) >= 0)
+                cgroup_bonding_migrate_to(u->cgroup_bondings, target, false);
+
+        cgroup_bonding_free(b, true);
+
+        /* Drop all attributes of this controller */
+        LIST_FOREACH_SAFE(by_unit, a, n, u->cgroup_attributes) {
+                if (!streq(a->controller, controller))
+                        continue;
+
+                unit_remove_drop_in(u, runtime, a->name);
+                cgroup_attribute_free(a);
+        }
+
+        return 0;
+}
+
+int bus_unit_cgroup_attribute_get(Unit *u, DBusMessageIter *iter, char ***_result) {
+        _cleanup_free_ char *controller = NULL;
+        CGroupAttribute *a;
+        CGroupBonding *b;
+        const char *name;
+        char **l = NULL;
+        int r;
+
+        assert(u);
+        assert(iter);
+        assert(_result);
+
+        if (!unit_get_exec_context(u))
+                return -EINVAL;
+
+        r = bus_iter_get_basic_and_next(iter, DBUS_TYPE_STRING, &name, false);
+        if (r < 0)
+                return r;
+
+        r = cg_controller_from_attr(name, &controller);
+        if (r < 0)
+                return r;
+
+        /* First attempt, read the value from the kernel */
+        b = cgroup_bonding_find_list(u->cgroup_bondings, controller);
+        if (b) {
+                _cleanup_free_ char *p = NULL, *v = NULL;
+
+                r = cg_get_path(b->controller, b->path, name, &p);
+                if (r < 0)
+                        return r;
+
+                r = read_full_file(p, &v, NULL);
+                if (r >= 0) {
+                        /* Split on new lines */
+                        l = strv_split_newlines(v);
+                        if (!l)
+                                return -ENOMEM;
+
+                        *_result = l;
+                        return 0;
+
+                }
+        }
+
+        /* If that didn't work, read our cached value */
+        LIST_FOREACH(by_unit, a, u->cgroup_attributes) {
+
+                if (!cgroup_attribute_matches(a, controller, name))
+                        continue;
+
+                r = strv_extend(&l, a->value);
+                if (r < 0) {
+                        strv_free(l);
+                        return r;
+                }
+        }
+
+        if (!l)
+                return -ENOENT;
+
+        *_result = l;
+        return 0;
+}
+
+static int update_attribute_drop_in(Unit *u, bool runtime, const char *name) {
+        _cleanup_free_ char *buf = NULL;
+        CGroupAttribute *a;
+
+        assert(u);
+        assert(name);
+
+        LIST_FOREACH(by_unit, a, u->cgroup_attributes) {
+                if (!cgroup_attribute_matches(a, NULL, name))
+                        continue;
+
+                if (!buf) {
+                        buf = strjoin("[", UNIT_VTABLE(u)->exec_section, "]\n"
+                                      "ControlGroupAttribute=", a->name, " ", a->value, "\n", NULL);
+
+                        if (!buf)
+                                return -ENOMEM;
+                } else {
+                        char *b;
+
+                        b = strjoin(buf,
+                                    "ControlGroupAttribute=", a->name, " ", a->value, "\n", NULL);
+
+                        if (!b)
+                                return -ENOMEM;
+
+                        free(buf);
+                        buf = b;
+                }
+        }
+
+        if (buf)
+                return unit_write_drop_in(u, runtime, name, buf);
+        else
+                return unit_remove_drop_in(u, runtime, name);
+}
+
+int bus_unit_cgroup_attribute_set(Unit *u, DBusMessageIter *iter) {
+        _cleanup_strv_free_ char **l = NULL;
+        int r;
+        bool runtime = false;
+        char **value;
+        const char *name;
+
+        assert(u);
+        assert(iter);
+
+        if (!unit_get_exec_context(u))
+                return -EINVAL;
+
+        r = bus_iter_get_basic_and_next(iter, DBUS_TYPE_STRING, &name, true);
+        if (r < 0)
+                return r;
+
+        r = bus_parse_strv_iter(iter, &l);
+        if (r < 0)
+                return r;
+
+        if (!dbus_message_iter_next(iter))
+                return -EINVAL;
+
+        r = parse_mode(iter, &runtime, false);
+        if (r < 0)
+                return r;
+
+        STRV_FOREACH(value, l) {
+                _cleanup_free_ char *v = NULL;
+                CGroupAttribute *a;
+                const CGroupSemantics *s;
+
+                r = cgroup_semantics_find(NULL, name, *value, &v, &s);
+                if (r < 0)
+                        return r;
+
+                if (s && !s->multiple && l[1])
+                        return -EINVAL;
+
+                r = unit_add_cgroup_attribute(u, s, NULL, name, v ? v : *value, &a);
+                if (r < 0)
+                        return r;
+
+                if (r > 0) {
+                        CGroupBonding *b;
+
+                        b = cgroup_bonding_find_list(u->cgroup_bondings, a->controller);
+                        if (!b) {
+                                /* Doesn't exist yet? Then let's add it */
+                                r = unit_add_cgroup_from_text(u, a->controller, false, &b);
+                                if (r < 0)
+                                        return r;
+
+                                if (r > 0) {
+                                        cgroup_bonding_realize(b);
+                                        cgroup_bonding_migrate(b, u->cgroup_bondings);
+                                }
+                        }
+
+                        /* Make it count */
+                        cgroup_attribute_apply(a, u->cgroup_bondings);
+                }
+
+        }
+
+        r = update_attribute_drop_in(u, runtime, name);
+        if (r < 0)
+                return r;
+
+        return 0;
+}
+
+int bus_unit_cgroup_attribute_unset(Unit *u, DBusMessageIter *iter) {
+        const char *name;
+        bool runtime;
+        int r;
+
+        assert(u);
+        assert(iter);
+
+        if (!unit_get_exec_context(u))
+                return -EINVAL;
+
+        r = bus_iter_get_basic_and_next(iter, DBUS_TYPE_STRING, &name, true);
+        if (r < 0)
+                return r;
+
+        r = parse_mode(iter, &runtime, false);
+        if (r < 0)
+                return r;
+
+        cgroup_attribute_free_some(u->cgroup_attributes, NULL, name);
+        update_attribute_drop_in(u, runtime, name);
+
+        return 0;
+}
+
 const BusProperty bus_unit_properties[] = {
         { "Id",                   bus_property_append_string,         "s", offsetof(Unit, id),                                         true },
         { "Names",                bus_unit_append_names,             "as", 0 },
         { "Following",            bus_unit_append_following,          "s", 0 },
+        { "Slice",                bus_unit_append_slice,              "s", 0 },
         { "Requires",             bus_unit_append_dependencies,      "as", offsetof(Unit, dependencies[UNIT_REQUIRES]),                true },
         { "RequiresOverridable",  bus_unit_append_dependencies,      "as", offsetof(Unit, dependencies[UNIT_REQUIRES_OVERRIDABLE]),    true },
         { "Requisite",            bus_unit_append_dependencies,      "as", offsetof(Unit, dependencies[UNIT_REQUISITE]),               true },
@@ -842,6 +1304,7 @@ const BusProperty bus_unit_properties[] = {
         { "SubState",             bus_unit_append_sub_state,          "s", 0 },
         { "FragmentPath",         bus_property_append_string,         "s", offsetof(Unit, fragment_path),                              true },
         { "SourcePath",           bus_property_append_string,         "s", offsetof(Unit, source_path),                                true },
+        { "DropInPaths",          bus_property_append_strv,          "as", offsetof(Unit, dropin_paths),                               true },
         { "UnitFileState",        bus_unit_append_file_state,         "s", 0 },
         { "InactiveExitTimestamp",bus_property_append_usec,           "t", offsetof(Unit, inactive_exit_timestamp.realtime)   },
         { "InactiveExitTimestampMonotonic", bus_property_append_usec, "t", offsetof(Unit, inactive_exit_timestamp.monotonic)  },
@@ -864,9 +1327,6 @@ const BusProperty bus_unit_properties[] = {
         { "OnFailureIsolate",     bus_property_append_bool,           "b", offsetof(Unit, on_failure_isolate)                 },
         { "IgnoreOnIsolate",      bus_property_append_bool,           "b", offsetof(Unit, ignore_on_isolate)                  },
         { "IgnoreOnSnapshot",     bus_property_append_bool,           "b", offsetof(Unit, ignore_on_snapshot)                 },
-        { "DefaultControlGroup",  bus_unit_append_default_cgroup,     "s", 0 },
-        { "ControlGroup",         bus_unit_append_cgroups,           "as", 0 },
-        { "ControlGroupAttributes", bus_unit_append_cgroup_attrs,"a(sss)", 0 },
         { "NeedDaemonReload",     bus_unit_append_need_daemon_reload, "b", 0 },
         { "JobTimeoutUSec",       bus_property_append_usec,           "t", offsetof(Unit, job_timeout)                        },
         { "ConditionTimestamp",   bus_property_append_usec,           "t", offsetof(Unit, condition_timestamp.realtime)       },
@@ -875,3 +1335,10 @@ const BusProperty bus_unit_properties[] = {
         { "LoadError",            bus_unit_append_load_error,      "(ss)", 0 },
         { NULL, }
 };
+
+const BusProperty bus_unit_cgroup_properties[] = {
+        { "DefaultControlGroup",    bus_unit_append_default_cgroup,     "s", 0 },
+        { "ControlGroups",          bus_unit_append_cgroups,           "as", 0 },
+        { "ControlGroupAttributes", bus_unit_append_cgroup_attrs,  "a(sss)", 0 },
+        { NULL, }
+};