Before, handling of global properties (set on systemd-udevd by `udevadm
control -p FOO=foo`) was inconsistent. They were honored in ENV matches,
but not in any assignment. This meant that any use of $env{FOO} (where
FOO was a global property) expanded to an empty string.
AFAICT there's no reason to keep removed entries in the Hashmap
(although it doesn't break anything either). The only use of this
hashmap is in udev_rule_apply_token_to_event(), which just retrieves the
value using hashmap_get(), hence there's no difference there between an
existing entry with a NULL value and a missing entry.
All the following commands would just fail with -ENOANO anyway, hence
there's no point in sending them. And it allows us to shave off some
error handling code.
This is mostly just refactoring to make the code more manageable and
extendable. It doesn't introduce any semantic changes, but it
"optimizes" the communication with udevd a bit:
* If an option is used multiple times, only one command will be sent. If
the option takes a value, the value of the final appearance of the
option is used. The only exception is --property, which is additive by
nature.
* Options --start-exec-queue and --stop-exec-queue are handled together.
Only one of START_QUEUE/STOP_QUEUE commands will be sent to udevd even
if both options appear on the command line.
This replaces the local implementation of a timeout file lock with our
new generic one.
Note that a comment in the old code claimed we couldn't use alarm()-like timeouts,
but htat's not entirely true: we can if we use SIGKILL, and thus know
for sure that the process will be dead in case the timer is hit before
we actually enter the file lock syscall. But we also know it will be
delivered if we hit after.
Sometimes it makes sense to hard kill a client if we die. Let's hence
add a third FORK_DEATHSIG flag for this purpose: FORK_DEATHSIG_SIGKILL.
To make things less confusing this also renames FORK_DEATHSIG to
FORK_DEATHSIG_SIGTERM to make clear it sends SIGTERM. We already had
FORK_DEATHSIG_SIGINT, hence this makes things nicely symmetric.
A bunch of users are switched over for FORK_DEATHSIG_SIGKILL where we
know it's safe to abort things abruptly. This should make some kernel
cases more robust, since we cannot get confused by signal masks or such.
While we are at it, also fix a bunch of bugs where we didn't take
FORK_DEATHSIG_SIGINT into account in safe_fork()
Currently the ID_NET_DRIVER is set in net_setup_link builtin.
But this is called pretty late in the udev processing chain.
Right now in some custom rules it was workarounded by calling ethtool
binary directly, which is ugly.
So let's split this code to a separate builtin.
Several udev rules depends on the previous behavior, i.e. that udev
replaces the devlink with the newer device node when the priority is
equivalent. Let's relax the optimization done by
331aa7aa15.
Follow-up for 331aa7aa15.
Note, the offending commit drops O(N) of file reads per uevent, and this
commit does not change the computational order. So, hopefully the
performance impact of this change is small enough.
Fixes#28141.
We use it for more than just pipe() arrays. For example also for
socketpair(). Hence let's give it a generic name.
Also add EBADF_TRIPLET to mirror this for things like
stdin/stdout/stderr arrays, which we use a bunch of times.
This is preparation for #28891, which adds a bunch more helpers around
"struct iovec", at which point this really deserves its own .c/.h file.
The idea is that we sooner or later can consider "struct iovec" as an
entirely generic mechanism to reference some binary blob, and is the
go-to type for this purpose whenever we need one.
This allows distros to install configuration file templates in /usr/lib/systemd
for example.
Currently we install "empty" config files in /etc/systemd/. They serve two
purposes:
- The file contains commented-out values that show the default settings.
- It is easier to edit the right file if it is already there, the user doesn't
have to type in the path correctly, and the basic file structure is already in
place so it's easier to edit.
Things that have happened since this approach was put in place:
- We started supporting drop-ins for config files, and drop-ins are the
recommended way to create local configuration overrides.
- We have systemd-analyze cat-config which takes care of iterating over
all possible locations (/etc, /run, /usr, /usr/local) and figuring out
the right file.
- Because of the first two points, systemd-analyze cat-config is much better,
because it takes care of finding all the drop-ins and figuring out the
precedence. Looking at files manually is still possible of course, but not
very convenient.
The disadvantages of the current approach with "empty" files in /etc:
- We clutter up /etc so it's harder to see what the local configuration actually is.
- If a user edits the file, package updates will not override the file (e.g.
systemd.rpm uses %config(noreplace). This means that the "documented defaults"
will become stale over time, if the user ever edits the main config file.
Thus, I think that it's reasonable to:
- Install the main config file to /usr/lib so that it serves as reference for
syntax and option names and default values and is properly updated on package
upgrades.
- Recommend to users to always use drop-ins for configuration and
systemd-analyze cat-config to view the documentation.
This setting makes this change opt-in.
Fixes#18420.
[zjs: add more text to the description]
Let's support the same filtering options that we also support in
udevadm trigger in udevadm info to filter the devices produced by
--export-db.
One difference is that all properties specified by --propery-match=
have to be satisfied in udevadm info unlike udevadm trigger where just
one of them has to be satisfied.
systemd's own cgroup hierarchy is special to us, we use it to actually
manage processes. Because of that many calls tha apply to cgroups are
only ever called with the SYSTEMD_CGROUP_CONTROLLER as controller
argument. Let's hence remove the argument altogether.
This in particular touches the kill and xattr routines.
This changes no behaviour, we just drop an argument that is always set
to the same value anyway.
This is preparation to eventually getting rid of the cgroupvs1, because
on cgroupvs2 the cgroup paths do not change for different controllers,
there's only a single hierarchy there.
We might need a lot of fds on large systems, hence raise RLIMIT_NOFILE
to what the service manager allows us, which is quite a lot these days.
udev already sets FORK_RLIMIT_NOFILE_SAFE when forking of chilren, thus
ensuring that forked off processes get their RLIMIT_NOFILE soft limit
reset to 1K for compat with crappy old select().
Replaces: #29298Fixes: #28583
path_simplify_full()/path_simplify() are changed to allow a NULL path, for
which a NULL is returned. Generally, callers have already asserted before that
the argument is nonnull. This way path_simplify_full()/path_simplify() and
path_simplify_alloc() behave consistently.
In sd-device.c, logging in device_set_syspath() is intentionally dropped: other
branches don't log.
In mount-tool.c, logging in parse_argv() is changed to log the user-specified
value, not the simplified string. In an error message, we should show the
actual argument we got, not some transformed version.
huyubiao
Yu Watanabe
David Tardon
Lennart Poettering
Luca Boccassi
Frantisek Sumsal
Lukas Nykryn
janana
Franck Bui
Zbigniew Jędrzejewski-Szmek
Daan De Meyer
NRK
Mike Yuan