This drops a good number of type-specific _cleanup_ macros, and patches
all users to just use the generic ones.
In most recent code we abstained from defining type-specific macros, and
this basically removes all those added already, with the exception of
the really low-level ones.
Having explicit macros for this is not too useful, as the expression
without the extra macro is generally just 2ch wider. We should generally
emphesize generic code, unless there are really good reasons for
specific code, hence let's follow this in this case too.
Note that _cleanup_free_ and similar really low-level, libc'ish, Linux
API'ish macros continue to be defined, only the really high-level OO
ones are dropped. From now on this should really be the rule: for really
low-level stuff, such as memory allocation, fd handling and so one, go
ahead and define explicit per-type macros, but for high-level, specific
program code, just use the generic _cleanup_() macro directly, in order
to keep things simple and as readable as possible for the uninitiated.
Note that before this patch some of the APIs (notable libudev ones) were
already used with the high-level macros at some places and with the
generic _cleanup_ macro at others. With this patch we hence unify on the
latter.
I'm not sure if I understand the original code. AFAICS, errno does not
have to be set at all in this callback.
ratelimit_test() returns positive if we are under limit. The code would only
log if the condition happened very often, which I assume is not inteded, and
this check was supposed to prevent too much logging.
Do not try to party initialize a device during deserialization if it's not
known by udev (anymore) and therefore hasn't been seen during device
enumeration.
The device unit in this case has not been initialized properly and setting it
in the "plugged" state can be confusing.
Actually this happens during every boots when PID switches to the new rootfs:
PID is reexecuted and enumerates devices but since udev is not running, the
list of enumerated devices is empty.
PID1 updates the state of device units upon 2 different events:
- when it processes an event sent by udev and in this case the device deps are
started if the device enters in the "plugged" state.
- when it enumerates all devices during its startup or when it is asked to
reload its configuration data but in this case the device deps (if any) are
not retroactively started.
When udev processes a new "add" kernel event, it first registers the new device
in its databases then sends an event to systemd.
If for any reason, systemd is asked to reload its configuration between the
previous 2 steps, it might see for the first time the new device while scanning
/sys for all devices. Only during a second step, udev will send the event for
the new device.
In this peculiar case the device deps wont be started (even though the device
is first seen by PID1).
Indeed when reloading its configurations, PID1 will put the device unit in the
"plugged" state but without starting the device deps. Thereafter PID1 will get
the event from udev for the new device but the device unit will be in "plugged"
state already therefore it won't see any need to start the device dependencies.
Rather than assuming that during the reloading of systemd manager configuration
all devices listed in udev DBs have been already processed and should be put in
the "plugged" state (done by device_coldplug()), this patch does that only for
devices which have been processed via an udev event (device_dispatch_io())
previously. In this case we set "d->found" to "DEVICE_FOUND_UDEV" and we make
also sure to no more initialize "d->found" while enumerating devices. Instead
this field is now saved/restored while devices are serialized.
Files which are installed as-is (any .service and other unit files, .conf
files, .policy files, etc), are left as is. My assumption is that SPDX
identifiers are not yet that well known, so it's better to retain the
extended header to avoid any doubt.
I also kept any copyright lines. We can probably remove them, but it'd nice to
obtain explicit acks from all involved authors before doing that.
The warning is not emitted for absolute paths like /dev/sda or /home, which are
converted to .device and .mount unit names without any fuss.
Most of the time it's unlikely that users use invalid unit names on purpose,
so let's warn them. Warnings are silenced when --quiet is used.
$ build/systemctl show -p Id hello@foo-bar/baz
Invalid unit name "hello@foo-bar/baz" was escaped as "hello@foo-bar-baz" (maybe you should use systemd-escape?)
Id=hello@foo-bar-baz.service
$ build/systemd-run --user --slice foo-bar/baz --unit foo-bar/foo true
Invalid unit name "foo-bar/foo" was escaped as "foo-bar-foo" (maybe you should use systemd-escape?)
Invalid unit name "foo-bar/baz" was escaped as "foo-bar-baz" (maybe you should use systemd-escape?)
Running as unit: foo-bar-foo.service
Fixes#8302.
udev-made .device aliases are not normal alias
They are full-fledged units which are linked to
the same sysfs path
we need to explicitely propagate reload to all
alias
Previously dependencies configured with SYSTEMD_WANTS would be collected
on a device unit as long as it was loaded. let's fix that, and remove
dependencies again when SYTEMD_WANTS changes.
This replaces the dependencies Set* objects by Hashmap* objects, where
the key is the depending Unit, and the value is a bitmask encoding why
the specific dependency was created.
The bitmask contains a number of different, defined bits, that indicate
why dependencies exist, for example whether they are created due to
explicitly configured deps in files, by udev rules or implicitly.
Note that memory usage is not increased by this change, even though we
store more information, as we manage to encode the bit mask inside the
value pointer each Hashmap entry contains.
Why this all? When we know how a dependency came to be, we can update
dependencies correctly when a configuration source changes but others
are left unaltered. Specifically:
1. We can fix UDEV_WANTS dependency generation: so far we kept adding
dependencies configured that way, but if a device lost such a
dependency we couldn't them again as there was no scheme for removing
of dependencies in place.
2. We can implement "pin-pointed" reload of unit files. If we know what
dependencies were created as result of configuration in a unit file,
then we know what to flush out when we want to reload it.
3. It's useful for debugging: "systemd-analyze dump" now shows
this information, helping substantially with understanding how
systemd's dependency tree came to be the way it came to be.
This reverts commit 0ffddc6e2c. That
causes a rather severe disruption of D-Bus and other services when e. g.
restarting local-fs.target (as spotted by the "storage" test regression).
Fixes#6834
When a device is unplugged all device units sharing the same sysfs path
pointing to that device are supposed to be removed.
However it didn't work since while iterating the device unit list containing
all the relevant units, each unit was removed during each iteration of
LIST_FOREACH. However LIST_FOREACH doesn't support this use case and
LIST_FOREACH_SAFE must be use instead.
Device is gone and most likely it will get garbage collected. However in
cases when it doesn't get gc'ed (because it is referenced by some
other unit, e.g. mount from fstab) we need to unset sysfs. This is
because when device appears next time, possibly, with different sysfs
path we need to update the sysfs path. Current code could end up caching
stale sysfs path forever.
In reality this is not a problem for normal disks (unless you swap them
during system runtime). However this issue causes failures to mount
filesystems on LVM where sysfs path depends on activation
order (i.e. logical volumes from volume group that is activated first
get assigned lower dm-X numbers and corresponding syspaths).
Fixes#6126.
device_setup_unit() might be called (when an event happened in
/proc/self/mountinfo for example) with a null 'dev' parameter. This
indicates that the device has been unplugged but the corresponding
mountpoint is still visible in /proc/self/mountinfo.
This patch makes sure we don't call device_is_bound_by_mounts() in
this case.
Fixes: #5025
Since commit 9d06297, mount units from mountinfo are not bound to their devices
anymore (they use the "Requires" dependency instead).
This has the following drawback: if a media is mounted and the eject button is
pressed then the media is unconditionally ejected leaving some inconsistent
states.
Since udev is the component that is reacting (no matter if the device is used
or not) to the eject button, users expect that udev at least try to unmount the
media properly.
This patch introduces a new property "SYSTEMD_MOUNT_DEVICE_BOUND". When set on
a block device, all units that requires this device will see their "Requires"
dependency upgraded to a "BindTo" one. This is currently only used by cdrom
devices.
This patch also gives the possibility to the user to restore the previous
behavior that is bind a mount unit to a device. This is achieved by passing the
"x-systemd.device-bound" option to mount(8). Please note that currently this is
not working because libmount treats the x-* options has comments therefore
they're not available in utab for later application retrievals.
We generally try to make our destructors robust regarding NULL pointers, much
in the same way as glibc's free(). Do this also for unit_free().
Follow-up for #4748.
Since a581e45ae8, there's a few function calls to
unit_new_for_name which will unit_free on failure. Prior to this commit,
a failure would result in calling unit_free with a NULL unit, and hit an
assertion failure, seen at least via device_setup_unit:
Assertion 'u' failed at src/core/unit.c:519, function unit_free(). Aborting.
Fixes#4747https://bugs.archlinux.org/task/51950
In contrast to all other unit types device units when queued just track
external state, they cannot effect state changes on their own. Hence unless a
client or other job waits for them there's no reason to keep them in the job
queue. This adds a concept of GC'ing jobs of this type as soon as no client or
other job waits for them anymore.
To ensure this works correctly we need to track which clients actually
reference a job (i.e. which ones enqueued it). Unfortunately that's pretty
nasty to do for direct connections, as sd_bus_track doesn't work for
them. For now, work around this, by simply remembering in a boolean that a job
was requested by a direct connection, and reset it when we notice the direct
connection is gone. This means the GC logic works fine, except that jobs are
not immediately removed when direct connections disconnect.
In the longer term, a rework of the bus logic should fix this properly. For now
this should be good enough, as GC works for fine all cases except this one, and
thus is a clear improvement over the previous behaviour.
Fixes: #1921
This adds a new invocation ID concept to the service manager. The invocation ID
identifies each runtime cycle of a unit uniquely. A new randomized 128bit ID is
generated each time a unit moves from and inactive to an activating or active
state.
The primary usecase for this concept is to connect the runtime data PID 1
maintains about a service with the offline data the journal stores about it.
Previously we'd use the unit name plus start/stop times, which however is
highly racy since the journal will generally process log data after the service
already ended.
The "invocation ID" kinda matches the "boot ID" concept of the Linux kernel,
except that it applies to an individual unit instead of the whole system.
The invocation ID is passed to the activated processes as environment variable.
It is additionally stored as extended attribute on the cgroup of the unit. The
latter is used by journald to automatically retrieve it for each log logged
message and attach it to the log entry. The environment variable is very easily
accessible, even for unprivileged services. OTOH the extended attribute is only
accessible to privileged processes (this is because cgroupfs only supports the
"trusted." xattr namespace, not "user."). The environment variable may be
altered by services, the extended attribute may not be, hence is the better
choice for the journal.
Note that reading the invocation ID off the extended attribute from journald is
racy, similar to the way reading the unit name for a logging process is.
This patch adds APIs to read the invocation ID to sd-id128:
sd_id128_get_invocation() may be used in a similar fashion to
sd_id128_get_boot().
PID1's own logging is updated to always include the invocation ID when it logs
information about a unit.
A new bus call GetUnitByInvocationID() is added that allows retrieving a bus
path to a unit by its invocation ID. The bus path is built using the invocation
ID, thus providing a path for referring to a unit that is valid only for the
current runtime cycleof it.
Outlook for the future: should the kernel eventually allow passing of cgroup
information along AF_UNIX/SOCK_DGRAM messages via a unique cgroup id, then we
can alter the invocation ID to be generated as hash from that rather than
entirely randomly. This way we can derive the invocation race-freely from the
messages.
Previously, we had two enums ManagerRunningAs and UnitFileScope, that were
mostly identical and converted from one to the other all the time. The latter
had one more value UNIT_FILE_GLOBAL however.
Let's simplify things, and remove ManagerRunningAs and replace it by
UnitFileScope everywhere, thus making the translation unnecessary. Introduce
two new macros MANAGER_IS_SYSTEM() and MANAGER_IS_USER() to simplify checking
if we are running in one or the user context.
In some cases we do not have a udev device when setting up a unit
(certainly the code gracefully handles this). However, we do
then go on to compare the path via path_equal which will assert
if a null value is passed in.
See https://bugs.mageia.org/show_bug.cgi?id=17766
Not sure if this is the correct fix, but it avoids the crash
systemd automatically mounts device unless 'noauto' is part of the
mount options. This can happen during boot if the device is plugged at
that time or later when the system is already running (the latter case
is not documented AFAICS).
After the systemd booted, I plugged my USB device which had an entry
in /etc/fstab with the default options and systemd automatically
mounted it.
However I noticed that if I unplugged and re-plugged the device the
automatic mounting of the device didn't work anymore: systemd didn't
notice that the device was re-plugged.
This was due to the device unit which was not recycled by the GC
during the unplug event because in the case of automounting, the mount
unit still referenced it. When the device was re-plugged, the old
device unit was reused but it still had the old sysfs path (amongst
other useful information).
Systemd was confused by the stalled sysfs path and decided to ignore
the plug event.
This patch fixes this issue by simply not doing the sanity checking on
the sysfs path if the device is in unplugged state.
The functionality of SYSTEMD_USER_WANTS that attaches dependencies to device
units from udev rules was broken since commit b2c23da8. I guess it was due to
a mass replace s/SYSTEMD_USER/MANAGER_USER/.
Snapshots were never useful or used for anything. Many systemd
developers that I spoke to at systemd.conf2015, didn't even know they
existed, so it is fairly safe to assume that this type can be deleted
without harm.
The fundamental problem with snapshots is that the state of the system
is dynamic, devices come and go, users log in and out, timers fire...
and restoring all units to some state from the past would "undo"
those changes, which isn't really possible.
Tested by creating a snapshot, running the new binary, and checking
that the transition did not cause errors, and the snapshot is gone,
and snapshots cannot be created anymore.
New systemctl says:
Unknown operation snapshot.
Old systemctl says:
Failed to create snapshot: Support for snapshots has been removed.
IgnoreOnSnaphost settings are warned about and ignored:
Support for option IgnoreOnSnapshot= has been removed and it is ignored
http://lists.freedesktop.org/archives/systemd-devel/2015-November/034872.html
We cannot handle enumeration failures in a sensible way, hence let's try
hard to continue without making such failures fatal, and log about it
with precise error messages.
