chiark / gitweb /
core: rework device state logic
[elogind.git] / src / core / swap.c
index 13e12ad67a1ea268938cc7dc8c8abd488fdcd2e6..de3a5d8b10f1755c23a941bd5e3dae654f569398 100644 (file)
 ***/
 
 #include <errno.h>
-#include <limits.h>
 #include <unistd.h>
-#include <fcntl.h>
 #include <sys/epoll.h>
 #include <sys/stat.h>
-#include <sys/swap.h>
 #include <libudev.h>
 
 #include "unit.h"
 #include "swap.h"
-#include "load-fragment.h"
-#include "load-dropin.h"
 #include "unit-name.h"
 #include "dbus-swap.h"
 #include "special.h"
-#include "bus-errors.h"
 #include "exit-status.h"
-#include "def.h"
 #include "path-util.h"
 #include "virt.h"
 #include "udev-util.h"
+#include "fstab-util.h"
 
 static const UnitActiveState state_translation_table[_SWAP_STATE_MAX] = {
         [SWAP_DEAD] = UNIT_INACTIVE,
@@ -209,8 +203,6 @@ static int swap_add_device_links(Swap *s) {
 }
 
 static int swap_add_default_dependencies(Swap *s) {
-        int r;
-
         assert(s);
 
         if (UNIT(s)->manager->running_as != SYSTEMD_SYSTEM)
@@ -219,19 +211,7 @@ static int swap_add_default_dependencies(Swap *s) {
         if (detect_container(NULL) > 0)
                 return 0;
 
-        r = unit_add_two_dependencies_by_name(UNIT(s), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_UMOUNT_TARGET, NULL, true);
-        if (r < 0)
-                return r;
-
-        if (!s->from_fragment)
-                /* The swap unit can either be for an alternative device name, in which
-                 * case we don't need to add the dependency on swap.target because this unit
-                 * is following a different unit which will have this dependency added,
-                 * or it can be derived from /proc/swaps, in which case it was started
-                 * manually, and should not become a dependency of swap.target. */
-                return 0;
-
-        return unit_add_two_dependencies_by_name_inverse(UNIT(s), UNIT_AFTER, UNIT_REQUIRES, SPECIAL_SWAP_TARGET, NULL, true);
+        return unit_add_two_dependencies_by_name(UNIT(s), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_UMOUNT_TARGET, NULL, true);
 }
 
 static int swap_verify(Swap *s) {
@@ -247,12 +227,12 @@ static int swap_verify(Swap *s) {
 
         b = unit_has_name(UNIT(s), e);
         if (!b) {
-                log_error_unit(UNIT(s)->id, "%s: Value of \"What\" and unit name do not match, not loading.", UNIT(s)->id);
+                log_unit_error(UNIT(s)->id, "%s: Value of \"What\" and unit name do not match, not loading.", UNIT(s)->id);
                 return -EINVAL;
         }
 
         if (s->exec_context.pam_name && s->kill_context.kill_mode != KILL_CONTROL_GROUP) {
-                log_error_unit(UNIT(s)->id, "%s has PAM enabled. Kill mode must be set to 'control-group'. Refusing to load.", UNIT(s)->id);
+                log_unit_error(UNIT(s)->id, "%s has PAM enabled. Kill mode must be set to 'control-group'. Refusing to load.", UNIT(s)->id);
                 return -EINVAL;
         }
 
@@ -351,7 +331,7 @@ static int swap_load(Unit *u) {
         return swap_verify(s);
 }
 
-static int swap_add_one(
+static int swap_setup_unit(
                 Manager *m,
                 const char *what,
                 const char *what_proc_swaps,
@@ -376,8 +356,10 @@ static int swap_add_one(
 
         if (u &&
             SWAP(u)->from_proc_swaps &&
-            !path_equal(SWAP(u)->parameters_proc_swaps.what, what_proc_swaps))
+            !path_equal(SWAP(u)->parameters_proc_swaps.what, what_proc_swaps)) {
+                log_error("Swap %s appeared twice with different device paths %s and %s", e, SWAP(u)->parameters_proc_swaps.what, what_proc_swaps);
                 return -EEXIST;
+        }
 
         if (!u) {
                 delete = true;
@@ -392,7 +374,7 @@ static int swap_add_one(
 
                 SWAP(u)->what = strdup(what);
                 if (!SWAP(u)->what) {
-                        r = log_oom();
+                        r = -ENOMEM;
                         goto fail;
                 }
 
@@ -420,11 +402,10 @@ static int swap_add_one(
         p->priority = priority;
 
         unit_add_to_dbus_queue(u);
-
         return 0;
 
 fail:
-        log_warning_unit(e, "Failed to load swap unit: %s", strerror(-r));
+        log_unit_warning_errno(e, r, "Failed to load swap unit: %m");
 
         if (delete && u)
                 unit_free(u);
@@ -432,7 +413,7 @@ fail:
         return r;
 }
 
-static int swap_process_new_swap(Manager *m, const char *device, int prio, bool set_flags) {
+static int swap_process_new(Manager *m, const char *device, int prio, bool set_flags) {
         _cleanup_udev_device_unref_ struct udev_device *d = NULL;
         struct udev_list_entry *item = NULL, *first = NULL;
         const char *dn;
@@ -441,7 +422,7 @@ static int swap_process_new_swap(Manager *m, const char *device, int prio, bool
 
         assert(m);
 
-        r = swap_add_one(m, device, device, prio, set_flags);
+        r = swap_setup_unit(m, device, device, prio, set_flags);
         if (r < 0)
                 return r;
 
@@ -457,7 +438,7 @@ static int swap_process_new_swap(Manager *m, const char *device, int prio, bool
         /* Add the main device node */
         dn = udev_device_get_devnode(d);
         if (dn && !streq(dn, device))
-                swap_add_one(m, dn, device, prio, set_flags);
+                swap_setup_unit(m, dn, device, prio, set_flags);
 
         /* Add additional units for all symlinks */
         first = udev_device_get_devlinks_list_entry(d);
@@ -478,7 +459,7 @@ static int swap_process_new_swap(Manager *m, const char *device, int prio, bool
                             st.st_rdev != udev_device_get_devnum(d))
                                 continue;
 
-                swap_add_one(m, p, device, prio, set_flags);
+                swap_setup_unit(m, p, device, prio, set_flags);
         }
 
         return r;
@@ -486,6 +467,7 @@ static int swap_process_new_swap(Manager *m, const char *device, int prio, bool
 
 static void swap_set_state(Swap *s, SwapState state) {
         SwapState old_state;
+        Swap *other;
 
         assert(s);
 
@@ -506,13 +488,22 @@ static void swap_set_state(Swap *s, SwapState state) {
         }
 
         if (state != old_state)
-                log_debug_unit(UNIT(s)->id,
+                log_unit_debug(UNIT(s)->id,
                                "%s changed %s -> %s",
                                UNIT(s)->id,
                                swap_state_to_string(old_state),
                                swap_state_to_string(state));
 
         unit_notify(UNIT(s), state_translation_table[old_state], state_translation_table[state], true);
+
+        /* If there other units for the same device node have a job
+           queued it might be worth checking again if it is runnable
+           now. This is necessary, since swap_start() refuses
+           operation with EAGAIN if there's already another job for
+           the same device node queued. */
+        LIST_FOREACH_OTHERS(same_devnode, other, s)
+                if (UNIT(other)->job)
+                        job_add_to_run_queue(UNIT(other)->job);
 }
 
 static int swap_coldplug(Unit *u) {
@@ -627,6 +618,7 @@ static int swap_spawn(Swap *s, ExecCommand *c, pid_t *_pid) {
         exec_params.confirm_spawn = UNIT(s)->manager->confirm_spawn;
         exec_params.cgroup_supported = UNIT(s)->manager->cgroup_supported;
         exec_params.cgroup_path = UNIT(s)->cgroup_path;
+        exec_params.cgroup_delegate = s->cgroup_context.delegate;
         exec_params.runtime_prefix = manager_get_runtime_prefix(UNIT(s)->manager);
         exec_params.unit_id = UNIT(s)->id;
 
@@ -649,7 +641,6 @@ static int swap_spawn(Swap *s, ExecCommand *c, pid_t *_pid) {
 
 fail:
         s->timer_event_source = sd_event_source_unref(s->timer_event_source);
-
         return r;
 }
 
@@ -687,7 +678,8 @@ static void swap_enter_signal(Swap *s, SwapState state, SwapResult f) {
         r = unit_kill_context(
                         UNIT(s),
                         &s->kill_context,
-                        state != SWAP_ACTIVATING_SIGTERM && state != SWAP_DEACTIVATING_SIGTERM,
+                        (state != SWAP_ACTIVATING_SIGTERM && state != SWAP_DEACTIVATING_SIGTERM) ?
+                        KILL_KILL : KILL_TERMINATE,
                         -1,
                         s->control_pid,
                         false);
@@ -710,77 +702,10 @@ static void swap_enter_signal(Swap *s, SwapState state, SwapResult f) {
         return;
 
 fail:
-        log_warning_unit(UNIT(s)->id,
-                         "%s failed to kill processes: %s", UNIT(s)->id, strerror(-r));
-
+        log_unit_warning_errno(UNIT(s)->id, r, "%s failed to kill processes: %m", UNIT(s)->id);
         swap_enter_dead(s, SWAP_FAILURE_RESOURCES);
 }
 
-static int mount_find_pri(const char *options, int *ret) {
-        const char *opt;
-        char *end;
-        unsigned long r;
-
-        assert(ret);
-
-        if (!options)
-                return 0;
-
-        opt = mount_test_option(options, "pri");
-        if (!opt)
-                return 0;
-
-        opt += strlen("pri");
-        if (*opt != '=')
-                return -EINVAL;
-
-        errno = 0;
-        r = strtoul(opt + 1, &end, 10);
-        if (errno > 0)
-                return -errno;
-
-        if (end == opt + 1 || (*end != ',' && *end != 0))
-                return -EINVAL;
-
-        *ret = (int) r;
-        return 1;
-}
-
-static int mount_find_discard(const char *options, char **ret) {
-        const char *opt;
-        char *ans;
-        size_t len;
-
-        assert(ret);
-
-        if (!options)
-                return 0;
-
-        opt = mount_test_option(options, "discard");
-        if (!opt)
-                return 0;
-
-        opt += strlen("discard");
-        if (*opt == ',' || *opt == '\0')
-                ans = strdup("all");
-        else {
-                if (*opt != '=')
-                        return -EINVAL;
-
-                len = strcspn(opt + 1, ",");
-                if (len == 0)
-                        return -EINVAL;
-
-                ans = strndup(opt + 1, len);
-        }
-
-        if (!ans)
-                return -ENOMEM;
-
-        *ret = ans;
-        return 1;
-}
-
 static void swap_enter_activating(Swap *s) {
         _cleanup_free_ char *discard = NULL;
         int r, priority = -1;
@@ -791,11 +716,12 @@ static void swap_enter_activating(Swap *s) {
         s->control_command = s->exec_command + SWAP_EXEC_ACTIVATE;
 
         if (s->from_fragment) {
-                mount_find_discard(s->parameters_fragment.options, &discard);
+                fstab_filter_options(s->parameters_fragment.options, "discard\0",
+                                     NULL, &discard, NULL);
 
                 priority = s->parameters_fragment.priority;
                 if (priority < 0)
-                        mount_find_pri(s->parameters_fragment.options, &priority);
+                        fstab_find_pri(s->parameters_fragment.options, &priority);
         }
 
         r = exec_command_set(s->control_command, "/sbin/swapon", NULL);
@@ -817,7 +743,7 @@ static void swap_enter_activating(Swap *s) {
                 if (streq(discard, "all"))
                         discard_arg = "--discard";
                 else
-                        discard_arg = strappenda("--discard=", discard);
+                        discard_arg = strjoina("--discard=", discard);
 
                 r = exec_command_append(s->control_command, discard_arg, NULL);
                 if (r < 0)
@@ -839,9 +765,7 @@ static void swap_enter_activating(Swap *s) {
         return;
 
 fail:
-        log_warning_unit(UNIT(s)->id,
-                         "%s failed to run 'swapon' task: %s",
-                         UNIT(s)->id, strerror(-r));
+        log_unit_warning_errno(UNIT(s)->id, r, "%s failed to run 'swapon' task: %m", UNIT(s)->id);
         swap_enter_dead(s, SWAP_FAILURE_RESOURCES);
 }
 
@@ -871,14 +795,12 @@ static void swap_enter_deactivating(Swap *s) {
         return;
 
 fail:
-        log_warning_unit(UNIT(s)->id,
-                         "%s failed to run 'swapoff' task: %s",
-                         UNIT(s)->id, strerror(-r));
+        log_unit_warning_errno(UNIT(s)->id, r, "%s failed to run 'swapoff' task: %m", UNIT(s)->id);
         swap_enter_active(s, SWAP_FAILURE_RESOURCES);
 }
 
 static int swap_start(Unit *u) {
-        Swap *s = SWAP(u);
+        Swap *s = SWAP(u), *other;
 
         assert(s);
 
@@ -900,9 +822,16 @@ static int swap_start(Unit *u) {
         if (detect_container(NULL) > 0)
                 return -EPERM;
 
+        /* If there's a job for another swap unit for the same node
+         * running, then let's not dispatch this one for now, and wait
+         * until that other job has finished. */
+        LIST_FOREACH_OTHERS(same_devnode, other, s)
+                if (UNIT(other)->job && UNIT(other)->job->state == JOB_RUNNING)
+                        return -EAGAIN;
+
         s->result = SWAP_SUCCESS;
         swap_enter_activating(s);
-        return 0;
+        return 1;
 }
 
 static int swap_stop(Unit *u) {
@@ -925,7 +854,7 @@ static int swap_stop(Unit *u) {
                 return -EPERM;
 
         swap_enter_deactivating(s);
-        return 0;
+        return 1;
 }
 
 static int swap_serialize(Unit *u, FILE *f, FDSet *fds) {
@@ -958,7 +887,7 @@ static int swap_deserialize_item(Unit *u, const char *key, const char *value, FD
 
                 state = swap_state_from_string(value);
                 if (state < 0)
-                        log_debug_unit(u->id, "Failed to parse state value %s", value);
+                        log_unit_debug(u->id, "Failed to parse state value %s", value);
                 else
                         s->deserialized_state = state;
         } else if (streq(key, "result")) {
@@ -966,14 +895,14 @@ static int swap_deserialize_item(Unit *u, const char *key, const char *value, FD
 
                 f = swap_result_from_string(value);
                 if (f < 0)
-                        log_debug_unit(u->id, "Failed to parse result value %s", value);
+                        log_unit_debug(u->id, "Failed to parse result value %s", value);
                 else if (f != SWAP_SUCCESS)
                         s->result = f;
         } else if (streq(key, "control-pid")) {
                 pid_t pid;
 
                 if (parse_pid(value, &pid) < 0)
-                        log_debug_unit(u->id, "Failed to parse control-pid value %s", value);
+                        log_unit_debug(u->id, "Failed to parse control-pid value %s", value);
                 else
                         s->control_pid = pid;
 
@@ -982,13 +911,13 @@ static int swap_deserialize_item(Unit *u, const char *key, const char *value, FD
 
                 id = swap_exec_command_from_string(value);
                 if (id < 0)
-                        log_debug_unit(u->id, "Failed to parse exec-command value %s", value);
+                        log_unit_debug(u->id, "Failed to parse exec-command value %s", value);
                 else {
                         s->control_command_id = id;
                         s->control_command = s->exec_command + id;
                 }
         } else
-                log_debug_unit(u->id, "Unknown serialization key '%s'", key);
+                log_unit_debug(u->id, "Unknown serialization key '%s'", key);
 
         return 0;
 }
@@ -1046,8 +975,8 @@ static void swap_sigchld_event(Unit *u, pid_t pid, int code, int status) {
                 s->control_command_id = _SWAP_EXEC_COMMAND_INVALID;
         }
 
-        log_full_unit(f == SWAP_SUCCESS ? LOG_DEBUG : LOG_NOTICE,
-                      u->id,
+        log_unit_full(u->id,
+                      f == SWAP_SUCCESS ? LOG_DEBUG : LOG_NOTICE,
                       "%s swap process exited, code=%s status=%i",
                       u->id, sigchld_code_to_string(code), status);
 
@@ -1089,38 +1018,38 @@ static int swap_dispatch_timer(sd_event_source *source, usec_t usec, void *userd
 
         case SWAP_ACTIVATING:
         case SWAP_ACTIVATING_DONE:
-                log_warning_unit(UNIT(s)->id, "%s activation timed out. Stopping.", UNIT(s)->id);
+                log_unit_warning(UNIT(s)->id, "%s activation timed out. Stopping.", UNIT(s)->id);
                 swap_enter_signal(s, SWAP_ACTIVATING_SIGTERM, SWAP_FAILURE_TIMEOUT);
                 break;
 
         case SWAP_DEACTIVATING:
-                log_warning_unit(UNIT(s)->id, "%s deactivation timed out. Stopping.", UNIT(s)->id);
+                log_unit_warning(UNIT(s)->id, "%s deactivation timed out. Stopping.", UNIT(s)->id);
                 swap_enter_signal(s, SWAP_DEACTIVATING_SIGTERM, SWAP_FAILURE_TIMEOUT);
                 break;
 
         case SWAP_ACTIVATING_SIGTERM:
                 if (s->kill_context.send_sigkill) {
-                        log_warning_unit(UNIT(s)->id, "%s activation timed out. Killing.", UNIT(s)->id);
+                        log_unit_warning(UNIT(s)->id, "%s activation timed out. Killing.", UNIT(s)->id);
                         swap_enter_signal(s, SWAP_ACTIVATING_SIGKILL, SWAP_FAILURE_TIMEOUT);
                 } else {
-                        log_warning_unit(UNIT(s)->id, "%s activation timed out. Skipping SIGKILL. Ignoring.", UNIT(s)->id);
+                        log_unit_warning(UNIT(s)->id, "%s activation timed out. Skipping SIGKILL. Ignoring.", UNIT(s)->id);
                         swap_enter_dead(s, SWAP_FAILURE_TIMEOUT);
                 }
                 break;
 
         case SWAP_DEACTIVATING_SIGTERM:
                 if (s->kill_context.send_sigkill) {
-                        log_warning_unit(UNIT(s)->id, "%s deactivation timed out. Killing.", UNIT(s)->id);
+                        log_unit_warning(UNIT(s)->id, "%s deactivation timed out. Killing.", UNIT(s)->id);
                         swap_enter_signal(s, SWAP_DEACTIVATING_SIGKILL, SWAP_FAILURE_TIMEOUT);
                 } else {
-                        log_warning_unit(UNIT(s)->id, "%s deactivation timed out. Skipping SIGKILL. Ignoring.", UNIT(s)->id);
+                        log_unit_warning(UNIT(s)->id, "%s deactivation timed out. Skipping SIGKILL. Ignoring.", UNIT(s)->id);
                         swap_enter_dead(s, SWAP_FAILURE_TIMEOUT);
                 }
                 break;
 
         case SWAP_ACTIVATING_SIGKILL:
         case SWAP_DEACTIVATING_SIGKILL:
-                log_warning_unit(UNIT(s)->id, "%s swap process still around after SIGKILL. Ignoring.", UNIT(s)->id);
+                log_unit_warning(UNIT(s)->id, "%s swap process still around after SIGKILL. Ignoring.", UNIT(s)->id);
                 swap_enter_dead(s, SWAP_FAILURE_TIMEOUT);
                 break;
 
@@ -1156,15 +1085,17 @@ static int swap_load_proc_swaps(Manager *m, bool set_flags) {
                         if (k == EOF)
                                 break;
 
-                        log_warning("Failed to parse /proc/swaps:%u", i);
+                        log_warning("Failed to parse /proc/swaps:%u.", i);
                         continue;
                 }
 
                 d = cunescape(dev);
                 if (!d)
-                        return -ENOMEM;
+                        return log_oom();
 
-                k = swap_process_new_swap(m, d, prio, set_flags);
+                device_found_node(m, d, true, DEVICE_FOUND_SWAP, set_flags);
+
+                k = swap_process_new(m, d, prio, set_flags);
                 if (k < 0)
                         r = k;
         }
@@ -1182,7 +1113,7 @@ static int swap_dispatch_io(sd_event_source *source, int fd, uint32_t revents, v
 
         r = swap_load_proc_swaps(m, true);
         if (r < 0) {
-                log_error("Failed to reread /proc/swaps: %s", strerror(-r));
+                log_error_errno(r, "Failed to reread /proc/swaps: %m");
 
                 /* Reset flags, just in case, for late calls */
                 LIST_FOREACH(units_by_type, u, m->units_by_type[UNIT_SWAP]) {
@@ -1216,6 +1147,9 @@ static int swap_dispatch_io(sd_event_source *source, int fd, uint32_t revents, v
                                 break;
                         }
 
+                        if (swap->what)
+                                device_found_node(m, swap->what, false, DEVICE_FOUND_SWAP, true);
+
                 } else if (swap->just_activated) {
 
                         /* New swap entry */
@@ -1260,11 +1194,7 @@ static Unit *swap_following(Unit *u) {
         if (s->from_fragment)
                 return NULL;
 
-        LIST_FOREACH_AFTER(same_devnode, other, s)
-                if (other->from_fragment)
-                        return UNIT(other);
-
-        LIST_FOREACH_BEFORE(same_devnode, other, s)
+        LIST_FOREACH_OTHERS(same_devnode, other, s)
                 if (other->from_fragment)
                         return UNIT(other);
 
@@ -1306,13 +1236,7 @@ static int swap_following_set(Unit *u, Set **_set) {
         if (!set)
                 return -ENOMEM;
 
-        LIST_FOREACH_AFTER(same_devnode, other, s) {
-                r = set_put(set, other);
-                if (r < 0)
-                        goto fail;
-        }
-
-        LIST_FOREACH_BEFORE(same_devnode, other, s) {
+        LIST_FOREACH_OTHERS(same_devnode, other, s) {
                 r = set_put(set, other);
                 if (r < 0)
                         goto fail;
@@ -1373,7 +1297,7 @@ fail:
         return r;
 }
 
-int swap_process_new_device(Manager *m, struct udev_device *dev) {
+int swap_process_device_new(Manager *m, struct udev_device *dev) {
         struct udev_list_entry *item = NULL, *first = NULL;
         _cleanup_free_ char *e = NULL;
         const char *dn;
@@ -1416,7 +1340,7 @@ int swap_process_new_device(Manager *m, struct udev_device *dev) {
         return r;
 }
 
-int swap_process_removed_device(Manager *m, struct udev_device *dev) {
+int swap_process_device_remove(Manager *m, struct udev_device *dev) {
         const char *dn;
         int r = 0;
         Swap *s;
@@ -1465,6 +1389,21 @@ static int swap_get_timeout(Unit *u, uint64_t *timeout) {
         return 1;
 }
 
+static bool swap_supported(Manager *m) {
+        static int supported = -1;
+
+        /* If swap support is not available in the kernel, or we are
+         * running in a container we don't support swap units, and any
+         * attempts to starting one should fail immediately. */
+
+        if (supported < 0)
+                supported =
+                        access("/proc/swaps", F_OK) >= 0 &&
+                        detect_container(NULL) <= 0;
+
+        return supported;
+}
+
 static const char* const swap_state_table[_SWAP_STATE_MAX] = {
         [SWAP_DEAD] = "dead",
         [SWAP_ACTIVATING] = "activating",
@@ -1551,6 +1490,7 @@ const UnitVTable swap_vtable = {
 
         .enumerate = swap_enumerate,
         .shutdown = swap_shutdown,
+        .supported = swap_supported,
 
         .status_message_formats = {
                 .starting_stopping = {