From c38c0e05767c5fd526368b63cebcdd5617332940 Mon Sep 17 00:00:00 2001

From: Michael Olbrich <m.olbrich@pengutronix.de>

Date: Tue, 14 Apr 2015 22:01:48 +0200

Subject: [PATCH] automount: add expire support

(cherry picked from commit deb0a77cf0b409141c4b116ae30becb3d878e1ad)

Resolves: #1354410

---

 man/systemd.automount.xml             |   8 ++

 man/systemd.mount.xml                 |   9 ++

 src/core/automount.c                  | 224 ++++++++++++++++++++++++++++++++--

 src/core/automount.h                  |   6 +-

 src/core/dbus-automount.c             |   1 +

 src/core/load-fragment-gperf.gperf.m4 |   1 +

 src/core/mount.c                      |  20 +--

 src/fstab-generator/fstab-generator.c |  28 +++++

 8 files changed, 269 insertions(+), 28 deletions(-)

diff --git a/man/systemd.automount.xml b/man/systemd.automount.xml

index b5b5885..9561590 100644

--- a/man/systemd.automount.xml

+++ b/man/systemd.automount.xml

@@ -135,6 +135,14 @@

         creating these directories. Takes an access mode in octal

         notation. Defaults to 0755.</para></listitem>

       </varlistentry>

+      <varlistentry>

+        <term><varname>TimeoutIdleSec=</varname></term>

+        <listitem><para>Configures an idleness timeout. Once the mount has been

+        idle for the specified time, systemd will attempt to unmount. Takes a

+        unit-less value in seconds, or a time span value such as "5min 20s".

+        Pass 0 to disable the timeout logic. The timeout is disabled by

+        default.</para></listitem>

+      </varlistentry>

     </variablelist>

   </refsect1>

diff --git a/man/systemd.mount.xml b/man/systemd.mount.xml

index 8e652e1..04ed1e1 100644

--- a/man/systemd.mount.xml

+++ b/man/systemd.mount.xml

@@ -178,6 +178,15 @@

       </varlistentry>

       <varlistentry>

+        <term><option>x-systemd.idle-timeout=</option></term>

+

+        <listitem><para>Configures the idleness timeout of the

+        automount unit. See <varname>TimeoutIdleSec=</varname> in

+        <citerefentry><refentrytitle>systemd.automount</refentrytitle><manvolnum>5</manvolnum></citerefentry>

+        for details.</para></listitem>

+      </varlistentry>

+

+      <varlistentry>

         <term><option>x-systemd.device-timeout=</option></term>

         <listitem><para>Configure how long systemd should wait for a

diff --git a/src/core/automount.c b/src/core/automount.c

index b391f61..4e06661 100644

--- a/src/core/automount.c

+++ b/src/core/automount.c

@@ -42,6 +42,7 @@

 #include "dbus-automount.h"

 #include "bus-util.h"

 #include "bus-error.h"

+#include "async.h"

 static const UnitActiveState state_translation_table[_AUTOMOUNT_STATE_MAX] = {

         [AUTOMOUNT_DEAD] = UNIT_INACTIVE,

@@ -50,6 +51,22 @@ static const UnitActiveState state_translation_table[_AUTOMOUNT_STATE_MAX] = {

         [AUTOMOUNT_FAILED] = UNIT_FAILED

 };

+struct expire_data {

+        int dev_autofs_fd;

+        int ioctl_fd;

+};

+

+static inline void expire_data_free(struct expire_data *data) {

+        if (!data)

+                return;

+

+        safe_close(data->dev_autofs_fd);

+        safe_close(data->ioctl_fd);

+        free(data);

+}

+

+DEFINE_TRIVIAL_CLEANUP_FUNC(struct expire_data*, expire_data_free);

+

 static int open_dev_autofs(Manager *m);

 static int automount_dispatch_io(sd_event_source *s, int fd, uint32_t events, void *userdata);

@@ -81,13 +98,16 @@ static void repeat_unmount(const char *path) {

         }

 }

+static int automount_send_ready(Automount *a, Set *tokens, int status);

+

 static void unmount_autofs(Automount *a) {

         assert(a);

         if (a->pipe_fd < 0)

                 return;

-        automount_send_ready(a, -EHOSTDOWN);

+        automount_send_ready(a, a->tokens, -EHOSTDOWN);

+        automount_send_ready(a, a->expire_tokens, -EHOSTDOWN);

         a->pipe_event_source = sd_event_source_unref(a->pipe_event_source);

         a->pipe_fd = safe_close(a->pipe_fd);

@@ -112,6 +132,10 @@ static void automount_done(Unit *u) {

         set_free(a->tokens);

         a->tokens = NULL;

+        set_free(a->expire_tokens);

+        a->expire_tokens = NULL;

+

+        a->expire_event_source = sd_event_source_unref(a->expire_event_source);

 }

 static int automount_add_mount_links(Automount *a) {

@@ -265,6 +289,7 @@ static int automount_coldplug(Unit *u, Hashmap *deferred_work) {

 }

 static void automount_dump(Unit *u, FILE *f, const char *prefix) {

+        char time_string[FORMAT_TIMESPAN_MAX];

         Automount *a = AUTOMOUNT(u);

         assert(a);

@@ -273,11 +298,13 @@ static void automount_dump(Unit *u, FILE *f, const char *prefix) {

                 "%sAutomount State: %s\n"

                 "%sResult: %s\n"

                 "%sWhere: %s\n"

-                "%sDirectoryMode: %04o\n",

+                "%sDirectoryMode: %04o\n"

+                "%sTimeoutIdleUSec: %s\n",

                 prefix, automount_state_to_string(a->state),

                 prefix, automount_result_to_string(a->result),

                 prefix, a->where,

-                prefix, a->directory_mode);

+                prefix, a->directory_mode,

+                prefix, format_timespan(time_string, FORMAT_TIMESPAN_MAX, a->timeout_idle_usec, USEC_PER_SEC));

 }

 static void automount_enter_dead(Automount *a, AutomountResult f) {

@@ -367,7 +394,7 @@ static int autofs_protocol(int dev_autofs_fd, int ioctl_fd) {

         return 0;

 }

-static int autofs_set_timeout(int dev_autofs_fd, int ioctl_fd, time_t sec) {

+static int autofs_set_timeout(int dev_autofs_fd, int ioctl_fd, usec_t usec) {

         struct autofs_dev_ioctl param;

         assert(dev_autofs_fd >= 0);

@@ -375,7 +402,9 @@ static int autofs_set_timeout(int dev_autofs_fd, int ioctl_fd, time_t sec) {

         init_autofs_dev_ioctl(¶m;;

         param.ioctlfd = ioctl_fd;

-        param.timeout.timeout = sec;

+

+        /* Convert to seconds, rounding up. */

+        param.timeout.timeout = (usec + USEC_PER_SEC - 1) / USEC_PER_SEC;

         if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_TIMEOUT, &param) < 0)

                 return -errno;

@@ -404,7 +433,7 @@ static int autofs_send_ready(int dev_autofs_fd, int ioctl_fd, uint32_t token, in

         return 0;

 }

-int automount_send_ready(Automount *a, int status) {

+static int automount_send_ready(Automount *a, Set *tokens, int status) {

         _cleanup_close_ int ioctl_fd = -1;

         unsigned token;

         int r;

@@ -412,7 +441,7 @@ int automount_send_ready(Automount *a, int status) {

         assert(a);

         assert(status <= 0);

-        if (set_isempty(a->tokens))

+        if (set_isempty(tokens))

                 return 0;

         ioctl_fd = open_ioctl_fd(UNIT(a)->manager->dev_autofs_fd, a->where, a->dev_id);

@@ -427,7 +456,7 @@ int automount_send_ready(Automount *a, int status) {

         r = 0;

         /* Autofs thankfully does not hand out 0 as a token */

-        while ((token = PTR_TO_UINT(set_steal_first(a->tokens)))) {

+        while ((token = PTR_TO_UINT(set_steal_first(tokens)))) {

                 int k;

                 /* Autofs fun fact II:

@@ -446,6 +475,55 @@ int automount_send_ready(Automount *a, int status) {

         return r;

 }

+int automount_update_mount(Automount *a, MountState old_state, MountState state) {

+        _cleanup_close_ int ioctl_fd = -1;

+

+        assert(a);

+

+        switch (state) {

+        case MOUNT_MOUNTED:

+        case MOUNT_REMOUNTING:

+                automount_send_ready(a, a->tokens, 0);

+                break;

+         case MOUNT_DEAD:

+         case MOUNT_UNMOUNTING:

+         case MOUNT_MOUNTING_SIGTERM:

+         case MOUNT_MOUNTING_SIGKILL:

+         case MOUNT_REMOUNTING_SIGTERM:

+         case MOUNT_REMOUNTING_SIGKILL:

+         case MOUNT_UNMOUNTING_SIGTERM:

+         case MOUNT_UNMOUNTING_SIGKILL:

+         case MOUNT_FAILED:

+                if (old_state != state)

+                        automount_send_ready(a, a->tokens, -ENODEV);

+                break;

+        default:

+                break;

+        }

+

+        switch (state) {

+        case MOUNT_DEAD:

+                automount_send_ready(a, a->expire_tokens, 0);

+                break;

+         case MOUNT_MOUNTING:

+         case MOUNT_MOUNTING_DONE:

+         case MOUNT_MOUNTING_SIGTERM:

+         case MOUNT_MOUNTING_SIGKILL:

+         case MOUNT_REMOUNTING_SIGTERM:

+         case MOUNT_REMOUNTING_SIGKILL:

+         case MOUNT_UNMOUNTING_SIGTERM:

+         case MOUNT_UNMOUNTING_SIGKILL:

+         case MOUNT_FAILED:

+                if (old_state != state)

+                        automount_send_ready(a, a->expire_tokens, -ENODEV);

+                break;

+        default:

+                break;

+        }

+

+        return 0;

+}

+

 static void automount_enter_waiting(Automount *a) {

         _cleanup_close_ int ioctl_fd = -1;

         int p[2] = { -1, -1 };

@@ -505,7 +583,7 @@ static void automount_enter_waiting(Automount *a) {

         if (r < 0)

                 goto fail;

-        r = autofs_set_timeout(dev_autofs_fd, ioctl_fd, 300);

+        r = autofs_set_timeout(dev_autofs_fd, ioctl_fd, a->timeout_idle_usec);

         if (r < 0)

                 goto fail;

@@ -537,6 +615,83 @@ fail:

         automount_enter_dead(a, AUTOMOUNT_FAILURE_RESOURCES);

 }

+static void *expire_thread(void *p) {

+        struct autofs_dev_ioctl param;

+        _cleanup_(expire_data_freep) struct expire_data *data = (struct expire_data*)p;

+        int r;

+

+        assert(data->dev_autofs_fd >= 0);

+        assert(data->ioctl_fd >= 0);

+

+        init_autofs_dev_ioctl(¶m;;

+        param.ioctlfd = data->ioctl_fd;

+

+        do {

+                r = ioctl(data->dev_autofs_fd, AUTOFS_DEV_IOCTL_EXPIRE, ¶m;;

+        } while (r >= 0);

+

+        if (errno != EAGAIN)

+                log_warning_errno(errno, "Failed to expire automount, ignoring: %m");

+

+        return NULL;

+}

+

+static int automount_start_expire(Automount *a);

+

+static int automount_dispatch_expire(sd_event_source *source, usec_t usec, void *userdata) {

+        Automount *a = AUTOMOUNT(userdata);

+        _cleanup_(expire_data_freep) struct expire_data *data = NULL;

+        int r;

+

+        assert(a);

+        assert(source == a->expire_event_source);

+

+        data = new0(struct expire_data, 1);

+        if (!data)

+                return log_oom();

+

+        data->ioctl_fd = -1;

+

+        data->dev_autofs_fd = fcntl(UNIT(a)->manager->dev_autofs_fd, F_DUPFD_CLOEXEC, 3);

+        if (data->dev_autofs_fd < 0)

+                return log_unit_error_errno(UNIT(a)->id, errno, "Failed to duplicate autofs fd: %m");

+

+        data->ioctl_fd = open_ioctl_fd(UNIT(a)->manager->dev_autofs_fd, a->where, a->dev_id);

+        if (data->ioctl_fd < 0)

+                return log_unit_error_errno(UNIT(a)->id, data->ioctl_fd, "Couldn't open autofs ioctl fd: %m");

+

+        r = asynchronous_job(expire_thread, data);

+        if (r < 0)

+                return log_unit_error_errno(UNIT(a)->id, r, "Failed to start expire job: %m");

+

+        data = NULL;

+

+        return automount_start_expire(a);

+}

+

+static int automount_start_expire(Automount *a) {

+        int r;

+        usec_t timeout;

+

+        assert(a);

+

+        timeout = now(CLOCK_MONOTONIC) + MAX(a->timeout_idle_usec/10, USEC_PER_SEC);

+

+        if (a->expire_event_source) {

+                r = sd_event_source_set_time(a->expire_event_source, timeout);

+                if (r < 0)

+                        return r;

+

+                return sd_event_source_set_enabled(a->expire_event_source, SD_EVENT_ONESHOT);

+        }

+

+        return sd_event_add_time(

+                        UNIT(a)->manager->event,

+                        &a->expire_event_source,

+                        CLOCK_MONOTONIC, timeout, 0,

+                        automount_dispatch_expire, a);

+}

+

 static void automount_enter_runnning(Automount *a) {

         _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;

         struct stat st;

@@ -549,7 +704,8 @@ static void automount_enter_runnning(Automount *a) {

         if (unit_stop_pending(UNIT(a))) {

                 log_unit_debug(UNIT(a)->id,

                                "Suppressing automount request on %s since unit stop is scheduled.", UNIT(a)->id);

-                automount_send_ready(a, -EHOSTDOWN);

+                automount_send_ready(a, a->tokens, -EHOSTDOWN);

+                automount_send_ready(a, a->expire_tokens, -EHOSTDOWN);

                 return;

         }

@@ -576,6 +732,10 @@ static void automount_enter_runnning(Automount *a) {

                 }

         }

+        r = automount_start_expire(a);

+        if (r < 0)

+                log_unit_warning_errno(UNIT(a)->id, r, "Failed to start expiration timer, ignoring: %m");

+

         automount_set_state(a, AUTOMOUNT_RUNNING);

         return;

@@ -629,6 +789,8 @@ static int automount_serialize(Unit *u, FILE *f, FDSet *fds) {

         SET_FOREACH(p, a->tokens, i)

                 unit_serialize_item_format(u, f, "token", "%u", PTR_TO_UINT(p));

+        SET_FOREACH(p, a->expire_tokens, i)

+                unit_serialize_item_format(u, f, "expire-token", "%u", PTR_TO_UINT(p));

         if (a->pipe_fd >= 0) {

                 int copy;

@@ -688,6 +850,22 @@ static int automount_deserialize_item(Unit *u, const char *key, const char *valu

                         if (r < 0)

                                 return r;

                 }

+        } else if (streq(key, "expire-token")) {

+                unsigned token;

+

+                if (safe_atou(value, &token) < 0)

+                        log_unit_debug(u->id, "Failed to parse token value %s", value);

+                else {

+                        r = set_ensure_allocated(&a->expire_tokens, NULL);

+                        if (r < 0) {

+                                log_oom();

+                                return 0;

+                        }

+

+                        r = set_put(a->expire_tokens, UINT_TO_PTR(token));

+                        if (r < 0)

+                                log_unit_error_errno(u->id, r, "Failed to add expire token to set: %m");

+                }

         } else if (streq(key, "pipe-fd")) {

                 int fd;

@@ -725,6 +903,7 @@ static bool automount_check_gc(Unit *u) {

 }

 static int automount_dispatch_io(sd_event_source *s, int fd, uint32_t events, void *userdata) {

+        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;

         union autofs_v5_packet_union packet;

         Automount *a = AUTOMOUNT(userdata);

         ssize_t l;

@@ -777,6 +956,31 @@ static int automount_dispatch_io(sd_event_source *s, int fd, uint32_t events, vo

                 automount_enter_runnning(a);

                 break;

+        case autofs_ptype_expire_direct:

+                log_unit_debug(UNIT(a)->id, "Got direct umount request on %s", a->where);

+

+                (void) sd_event_source_set_enabled(a->expire_event_source, SD_EVENT_OFF);

+

+                r = set_ensure_allocated(&a->expire_tokens, NULL);

+                if (r < 0) {

+                        log_unit_error(UNIT(a)->id, "Failed to allocate token set.");

+                        goto fail;

+                }

+

+                r = set_put(a->expire_tokens, UINT_TO_PTR(packet.v5_packet.wait_queue_token));

+                if (r < 0) {

+                        log_unit_error_errno(UNIT(a)->id, r, "Failed to remember token: %m");

+                        goto fail;

+                }

+                r = manager_add_job(UNIT(a)->manager, JOB_STOP, UNIT_TRIGGER(UNIT(a)), JOB_REPLACE, true, &error, NULL);

+                if (r < 0) {

+                        log_unit_warning(UNIT(a)->id,

+                                         "%s failed to queue umount startup job: %s",

+                                         UNIT(a)->id, bus_error_message(&error, r));

+                        goto fail;

+                }

+                break;

+

         default:

                 log_unit_error(UNIT(a)->id, "Received unknown automount request %i", packet.hdr.type);

                 break;

diff --git a/src/core/automount.h b/src/core/automount.h

index 60f5522..2a50fef 100644

--- a/src/core/automount.h

+++ b/src/core/automount.h

@@ -47,6 +47,7 @@ struct Automount {

         AutomountState state, deserialized_state;

         char *where;

+        usec_t timeout_idle_usec;

         int pipe_fd;

         sd_event_source *pipe_event_source;

@@ -54,13 +55,16 @@ struct Automount {

         dev_t dev_id;

         Set *tokens;

+        Set *expire_tokens;

+

+        sd_event_source *expire_event_source;

         AutomountResult result;

 };

 extern const UnitVTable automount_vtable;

-int automount_send_ready(Automount *a, int status);

+int automount_update_mount(Automount *a, MountState old_state, MountState state);

 const char* automount_state_to_string(AutomountState i) _const_;

 AutomountState automount_state_from_string(const char *s) _pure_;

diff --git a/src/core/dbus-automount.c b/src/core/dbus-automount.c

index b2a510a..c62ad82 100644

--- a/src/core/dbus-automount.c

+++ b/src/core/dbus-automount.c

@@ -32,5 +32,6 @@ const sd_bus_vtable bus_automount_vtable[] = {

         SD_BUS_PROPERTY("Where", "s", NULL, offsetof(Automount, where), SD_BUS_VTABLE_PROPERTY_CONST),

         SD_BUS_PROPERTY("DirectoryMode", "u", bus_property_get_mode, offsetof(Automount, directory_mode), SD_BUS_VTABLE_PROPERTY_CONST),

         SD_BUS_PROPERTY("Result", "s", property_get_result, offsetof(Automount, result), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),

+        SD_BUS_PROPERTY("TimeoutIdleUSec", "t", bus_property_get_usec, offsetof(Automount, timeout_idle_usec), SD_BUS_VTABLE_PROPERTY_CONST),

         SD_BUS_VTABLE_END

 };

diff --git a/src/core/load-fragment-gperf.gperf.m4 b/src/core/load-fragment-gperf.gperf.m4

index f3a6e13..c866a9c 100644

--- a/src/core/load-fragment-gperf.gperf.m4

+++ b/src/core/load-fragment-gperf.gperf.m4

@@ -318,6 +318,7 @@ KILL_CONTEXT_CONFIG_ITEMS(Mount)m4_dnl

 m4_dnl

 Automount.Where,                 config_parse_path,                  0,                             offsetof(Automount, where)

 Automount.DirectoryMode,         config_parse_mode,                  0,                             offsetof(Automount, directory_mode)

+Automount.TimeoutIdleSec,        config_parse_sec,                   0,                             offsetof(Automount, timeout_idle_usec)

 m4_dnl

 Swap.What,                       config_parse_path,                  0,                             offsetof(Swap, parameters_fragment.what)

 Swap.Priority,                   config_parse_int,                   0,                             offsetof(Swap, parameters_fragment.priority)

diff --git a/src/core/mount.c b/src/core/mount.c

index 3fbdb7d..7ca7f5a 100644

--- a/src/core/mount.c

+++ b/src/core/mount.c

@@ -552,7 +552,7 @@ static int mount_load(Unit *u) {

         return mount_verify(m);

 }

-static int mount_notify_automount(Mount *m, int status) {

+static int mount_notify_automount(Mount *m, MountState old_state, MountState state) {

         Unit *p;

         int r;

         Iterator i;

@@ -561,7 +561,7 @@ static int mount_notify_automount(Mount *m, int status) {

         SET_FOREACH(p, UNIT(m)->dependencies[UNIT_TRIGGERED_BY], i)

                 if (p->type == UNIT_AUTOMOUNT) {

-                         r = automount_send_ready(AUTOMOUNT(p), status);

+                         r = automount_update_mount(AUTOMOUNT(p), old_state, state);

                          if (r < 0)

                                  return r;

                 }

@@ -592,21 +592,7 @@ static void mount_set_state(Mount *m, MountState state) {

                 m->control_command_id = _MOUNT_EXEC_COMMAND_INVALID;

         }

-        if (state == MOUNT_MOUNTED ||

-            state == MOUNT_REMOUNTING)

-                mount_notify_automount(m, 0);

-        else if (state == MOUNT_DEAD ||

-                 state == MOUNT_UNMOUNTING ||

-                 state == MOUNT_MOUNTING_SIGTERM ||

-                 state == MOUNT_MOUNTING_SIGKILL ||

-                 state == MOUNT_REMOUNTING_SIGTERM ||

-                 state == MOUNT_REMOUNTING_SIGKILL ||

-                 state == MOUNT_UNMOUNTING_SIGTERM ||

-                 state == MOUNT_UNMOUNTING_SIGKILL ||

-                 state == MOUNT_FAILED) {

-                if (state != old_state)

-                        mount_notify_automount(m, -ENODEV);

-        }

+        mount_notify_automount(m, old_state, state);

         if (state != old_state)

                 log_unit_debug(UNIT(m)->id,

diff --git a/src/fstab-generator/fstab-generator.c b/src/fstab-generator/fstab-generator.c

index 029eb16..a943393 100644

--- a/src/fstab-generator/fstab-generator.c

+++ b/src/fstab-generator/fstab-generator.c

@@ -213,6 +213,30 @@ static int write_requires_mounts_for(FILE *f, const char *opts) {

         return 0;

 }

+

+static int write_idle_timeout(FILE *f, const char *where, const char *opts, char **filtered) {

+        _cleanup_free_ char *timeout = NULL;

+        char timespan[FORMAT_TIMESPAN_MAX];

+        usec_t u;

+        int r;

+

+        r = fstab_filter_options(opts, "x-systemd.idle-timeout\0", NULL, &timeout, filtered);

+        if (r < 0)

+                return log_warning_errno(r, "Failed to parse options: %m");

+        if (r == 0)

+                return 0;

+

+        r = parse_sec(timeout, &u);

+        if (r < 0) {

+                log_warning("Failed to parse timeout for %s, ignoring: %s", where, timeout);

+                return 0;

+        }

+

+        fprintf(f, "TimeoutIdleSec=%s\n", format_timespan(timespan, sizeof(timespan), u, 0));

+

+        return 0;

+}

+

 static int add_mount(

                 const char *what,

                 const char *where,

@@ -374,6 +398,10 @@ static int add_mount(

                         "Where=%s\n",

                         where);

+                r = write_idle_timeout(f, where, opts, &filtered);

+                if (r < 0)

+                        return r;

+

                 fflush(f);

                 if (ferror(f))

                         return log_error_errno(errno, "Failed to write unit file %s: %m", automount_unit);