core: clean up errors for live mounting

* Use SD_BUS_ERROR_NOT_SUPPORTED where appropriate
* Use Service object in service_can_live_mount()
* Include errno in bus error message

diff --git a/src/core/service.c b/src/core/service.c
index d33abd16823b44d45a19f679d77aa0e829e67e63..1ac158f1eab608cc719fe9c1d6beeef197f57604 100644 (file)
--- a/src/core/service.c
+++ b/src/core/service.c
@@ -5167,7 +5167,8 @@ static int service_can_clean(Unit *u, ExecCleanMask *ret) {
         return 0;
 }
 
-static int service_live_mount(Unit *u,
+static int service_live_mount(
+                Unit *u,
                 const char *src,
                 const char *dst,
                 sd_bus_message *message,
@@ -5175,9 +5176,8 @@ static int service_live_mount(Unit *u,
                 const MountOptions *options,
                 sd_bus_error *error) {
 
-        _cleanup_(pidref_done) PidRef worker = PIDREF_NULL;
         Service *s = ASSERT_PTR(SERVICE(u));
-        const char *propagate_directory;
+        _cleanup_(pidref_done) PidRef worker = PIDREF_NULL;
         int r;
 
         assert(u);
@@ -5188,7 +5188,7 @@ static int service_live_mount(Unit *u,
         assert(!s->mount_request);
 
         if (s->state != SERVICE_RUNNING || !pidref_is_set(&s->main_pid)) {
-                log_unit_warning(u, "Service is not running, cannot live mount");
+                log_unit_warning(u, "Service is not running, cannot live mount.");
                 return sd_bus_error_setf(
                                 error,
                                 BUS_ERROR_UNIT_INACTIVE,
@@ -5199,7 +5199,7 @@ static int service_live_mount(Unit *u,
         }
 
         if (mount_point_is_credentials(u->manager->prefix[EXEC_DIRECTORY_RUNTIME], dst)) {
-                log_unit_warning(u, "Refusing to live mount over credential mount '%s'", dst);
+                log_unit_warning(u, "Refusing to live mount over credential mount '%s'.", dst);
                 return sd_bus_error_setf(
                                 error,
                                 SD_BUS_ERROR_INVALID_ARGS,
@@ -5210,7 +5210,7 @@ static int service_live_mount(Unit *u,
         }
 
         if (path_startswith_strv(dst, s->exec_context.inaccessible_paths)) {
-                log_unit_warning(u, "%s is not accessible to this unit, cannot live mount", dst);
+                log_unit_warning(u, "%s is not accessible to this unit, cannot live mount.", dst);
                 return sd_bus_error_setf(
                                 error,
                                 SD_BUS_ERROR_INVALID_ARGS,
@@ -5227,18 +5227,14 @@ static int service_live_mount(Unit *u,
 
         r = service_arm_timer(s, /* relative= */ true, s->timeout_start_usec);
         if (r < 0) {
-                log_unit_warning_errno(u, r, "Failed to install timer: %m");
-                sd_bus_error_set_errnof(
-                                error,
-                                r,
-                                "Live mounting '%s' on '%s' for unit '%s' cannot be scheduled: failed to install timer",
-                                src,
-                                dst,
-                                u->id);
+                log_unit_error_errno(u, r, "Failed to install timer: %m");
+                sd_bus_error_set_errnof(error, r,
+                                        "Live mounting '%s' on '%s' for unit '%s': failed to install timer: %m",
+                                        src, dst, u->id);
                 goto fail;
         }
 
-        propagate_directory = strjoina("/run/systemd/propagate/", u->id);
+        const char *propagate_directory = strjoina("/run/systemd/propagate/", u->id);
 
         /* Given we are running from PID1, avoid doing potentially heavy I/O operations like opening images
          * directly, and instead fork a worker process. We record the D-Bus message, so that we can reply
@@ -5246,19 +5242,12 @@ static int service_live_mount(Unit *u,
          * resource is available (or the operation failed) once they receive the response. */
         r = unit_fork_helper_process(u, "(sd-mount-in-ns)", /* into_cgroup= */ false, &worker);
         if (r < 0) {
-                log_unit_warning_errno(
-                                u,
-                                r,
-                                "Failed to fork process to mount '%s' on '%s' in unit's namespace: %m",
-                                src,
-                                dst);
-                sd_bus_error_set_errnof(
-                                error,
-                                r,
-                                "Live mounting '%s' on '%s' for unit '%s' cannot be scheduled: failed to fork process",
-                                src,
-                                dst,
-                                u->id);
+                log_unit_error_errno(u, r,
+                                     "Failed to fork process to mount '%s' on '%s' in unit's namespace: %m",
+                                     src, dst);
+                sd_bus_error_set_errnof(error, r,
+                                        "Live mounting '%s' on '%s' for unit '%s': failed to fork off helper process into namespace: %m",
+                                        src, dst, u->id);
                 goto fail;
         }
         if (r == 0) {
@@ -5279,26 +5268,21 @@ static int service_live_mount(Unit *u,
                                         src, dst,
                                         flags);
                 if (r < 0)
-                        log_unit_warning_errno(
-                                        u,
-                                        r,
-                                        "Failed to mount '%s' on '%s' in unit's namespace: %m",
-                                        src,
-                                        dst);
+                        log_unit_error_errno(u, r,
+                                             "Failed to mount '%s' on '%s' in unit's namespace: %m",
+                                             src, dst);
                 else
                         log_unit_debug(u, "Mounted '%s' on '%s' in unit's namespace", src, dst);
+
                 _exit(r < 0 ? EXIT_FAILURE : EXIT_SUCCESS);
         }
 
         r = unit_watch_pidref(u, &worker, /* exclusive= */ true);
         if (r < 0) {
-                sd_bus_error_set_errnof(
-                                error,
-                                r,
-                                "Live mounting '%s' on '%s' for unit '%s' failed: failed to watch worker process",
-                                src,
-                                dst,
-                                u->id);
+                log_unit_warning_errno(u, r, "Failed to watch live mount helper process: %m");
+                sd_bus_error_set_errnof(error, r,
+                                        "Live mounting '%s' on '%s' for unit '%s': failed to watch live mount helper process: %m",
+                                        src, dst, u->id);
                 goto fail;
         }
 
@@ -5313,11 +5297,11 @@ fail:
         return r;
 }
 
-static int service_can_live_mount(const Unit *u, sd_bus_error *error) {
-        assert(u);
+static int service_can_live_mount(Unit *u, sd_bus_error *error) {
+        Service *s = ASSERT_PTR(SERVICE(u));
 
         /* Ensure that the unit runs in a private mount namespace */
-        if (!exec_needs_mount_namespace(unit_get_exec_context(u), /* params= */ NULL, unit_get_exec_runtime(u)))
+        if (!exec_needs_mount_namespace(&s->exec_context, /* params= */ NULL, s->exec_runtime))
                 return sd_bus_error_setf(
                                 error,
                                 SD_BUS_ERROR_INVALID_ARGS,

diff --git a/src/core/unit.c b/src/core/unit.c
index 230a782631af733c1d1dbf89fd17fe09cebbbf0b..d0e62c4d884f5fb5904d681a839356f369c9adc5 100644 (file)
--- a/src/core/unit.c
+++ b/src/core/unit.c
@@ -6397,22 +6397,21 @@ Condition *unit_find_failed_condition(Unit *u) {
         return failed_trigger && !has_succeeded_trigger ? failed_trigger : NULL;
 }
 
-int unit_can_live_mount(const Unit *u, sd_bus_error *error) {
+int unit_can_live_mount(Unit *u, sd_bus_error *error) {
         assert(u);
 
         if (!UNIT_VTABLE(u)->live_mount)
                 return sd_bus_error_setf(
                                 error,
-                                SD_BUS_ERROR_INVALID_ARGS,
-                                "Live mounting not supported for unit type '%s' of unit '%s'.",
-                                unit_type_to_string(u->type),
-                                u->id);
+                                SD_BUS_ERROR_NOT_SUPPORTED,
+                                "Live mounting not supported by unit type '%s'",
+                                unit_type_to_string(u->type));
 
         if (u->load_state != UNIT_LOADED)
                 return sd_bus_error_setf(
                                 error,
                                 BUS_ERROR_NO_SUCH_UNIT,
-                                "Unit '%s' not loaded, cannot live mount.",
+                                "Unit '%s' not loaded, cannot live mount",
                                 u->id);
 
         if (!UNIT_VTABLE(u)->can_live_mount)
@@ -6434,7 +6433,7 @@ int unit_live_mount(
         assert(UNIT_VTABLE(u)->live_mount);
 
         if (!UNIT_IS_ACTIVE_OR_RELOADING(unit_active_state(u))) {
-                log_unit_debug(u, "Unit not active");
+                log_unit_debug(u, "Unit not active, cannot perform live mount.");
                 return sd_bus_error_setf(
                                 error,
                                 BUS_ERROR_UNIT_INACTIVE,
@@ -6445,7 +6444,7 @@ int unit_live_mount(
         }
 
         if (unit_active_state(u) == UNIT_REFRESHING) {
-                log_unit_debug(u, "Unit already live mounting");
+                log_unit_debug(u, "Unit already live mounting, refusing further requests.");
                 return sd_bus_error_setf(
                                 error,
                                 BUS_ERROR_UNIT_BUSY,

diff --git a/src/core/unit.h b/src/core/unit.h
index 5ffd82b67eb3ef941f76686d05e286720910584a..01e1adf961ed9a041a22138899ec32286bf462fc 100644 (file)
--- a/src/core/unit.h
+++ b/src/core/unit.h
@@ -587,7 +587,7 @@ typedef struct UnitVTable {
 
         /* Add a bind/image mount into the unit namespace while it is running. */
         int (*live_mount)(Unit *u, const char *src, const char *dst, sd_bus_message *message, MountInNamespaceFlags flags, const MountOptions *options, sd_bus_error *error);
-        int (*can_live_mount)(const Unit *u, sd_bus_error *error);
+        int (*can_live_mount)(Unit *u, sd_bus_error *error);
 
         /* Serialize state and file descriptors that should be carried over into the new
          * instance after reexecution. */
@@ -650,7 +650,7 @@ typedef struct UnitVTable {
         int (*bus_commit_properties)(Unit *u);
 
         /* Return the unit this unit is following */
-        Unit *(*following)(Unit *u);
+        Unit* (*following)(Unit *u);
 
         /* Return the set of units that are following each other */
         int (*following_set)(Unit *u, Set **s);
@@ -1047,7 +1047,7 @@ void unit_next_freezer_state(Unit *u, FreezerAction action, FreezerState *ret_ne
 void unit_set_freezer_state(Unit *u, FreezerState state);
 void unit_freezer_complete(Unit *u, FreezerState kernel_state);
 
-int unit_can_live_mount(const Unit *u, sd_bus_error *error);
+int unit_can_live_mount(Unit *u, sd_bus_error *error);
 int unit_live_mount(Unit *u, const char *src, const char *dst, sd_bus_message *message, MountInNamespaceFlags flags, const MountOptions *options, sd_bus_error *error);
 
 Condition *unit_find_failed_condition(Unit *u);