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The systemd-modeset tool is meant to debug grdev issues. It simply
displays morphing colors on any found display. This is pretty handy to
look for tearing in the backends and debug hotplug issues.
Note that this tool requires systemd-logind to be compiled from git
(there're important fixes that haven't been released, yet).
The grdev-drm backend manages DRM cards for grdev. Any DRM card with
DUMB_BUFFER support can be used. So far, our policy is to configure all
available connectors, but keep pipes inactive as long as users don't
enable the displays on top.
We hard-code double-buffering so far, but can easily support
single-buffering or n-buffering. We also require XRGB8888 as format as
this is required to be supported by all DRM drivers and it is what VTs
use. This allows us to switch from VTs to grdev via page-flips instead of
deep modesets.
There is still a lot room for improvements in this backend, but it works
smoothly so far so more enhanced features can be added later.
The grdev layer provides graphics-device access via the
libsystemd-terminal library. It will be used by all terminal helpers to
actually access display hardware.
Like idev, the grdev layer is built around session objects. On each
session object you add/remove graphics devices as they appear and vanish.
Any device type can be supported via specific card-backends. The exported
grdev API hides any device details.
Graphics devices are represented by "cards". Those are hidden in the
session and any pipe-configuration is automatically applied. Out of those,
we configure displays which are then exported to the API user. Displays
are meant as lowest hardware entity available outside of grdev. The
underlying pipe configuration is fully hidden and not accessible from the
outside. The grdev tiling layer allows almost arbitrary setups out of
multiple pipes, but so far we only use a small subset of this. More will
follow.
A grdev-display is meant to represent real connected displays/monitors.
The upper level screen arrangements are user policy and not controlled by
grdev. Applications are free to apply any policy they want.
Real card-backends will follow in later patches.
Rather than forcing gcc to always produce colorized error messages
whether on tty or not, enable automatic colorization by ensuring
GCC_COLORS is set to a non-empty string.
Doing it this way removes the need for workarounds in ~/.emacs or
~/.vimrc for "M-x compile" or ":make", respectively, to work.
Like systemd-subterm, this new systemd-evcat tool should only be used to
debug libsystemd-terminal. systemd-evcat attaches to the running session
and pushes all evdev devices attached to the current session into an
idev-session. All events of the created idev-devices are then printed to
stdout for input-event debugging.
The idev-keyboard object provides keyboard devices to the idev interface.
It uses libxkbcommon to provide proper keymap support.
So far, the keyboard implementation is pretty straightforward with one
keyboard device per matching evdev element. We feed everything into the
system keymap and provide proper high-level keyboard events to the
application. Compose-features and IM need to be added later.
The evdev-element provides linux evdev interfaces as idev-elements. This
way, all real input hardware devices on linux can be used with the idev
interface.
We use libevdev to interface with the kernel. It's a simple wrapper
library around the kernel evdev API that takes care to resync devices
after kernel-queue overflows, which is a rather non-trivial task.
Furthermore, it's a well tested interface used by all other major input
users (Xorg, weston, libinput, ...).
Last but not least, it provides nice keycode to keyname lookup tables (and
vice versa), which is really nice for debugging input problems.
The idev-interface provides input drivers for all libsystemd-terminal
based applications. It is split into 4 main objects:
idev_context: The context object tracks global state of the input
interface. This will include data like system-keymaps,
xkb contexts and more.
idev_session: A session serves as controller for a set of devices.
Each session on an idev-context is independent of each
other. The session is also the main notification object.
All events raised via idev are reported through the
session interface. Apart of that, the session is a
pretty dumb object that just contains devices.
idev_element: Elements provide real hardware in the idev stack. For
each hardware device, one element is added. Elements
have no knowledge of higher-level device types, they
only provide raw input data to the upper levels. For
example, each evdev device is represented by a different
element in an idev session.
idev_device: Devices are objects that the application deals with. An
application is usually not interested in elements (and
those are hidden to applications), instead, they want
high-level input devices like keyboard, touchpads, mice
and more. Device are the high-level interface provided
by idev. Each device might be fed by a set of elements.
Elements drive the device. If elements are removed,
devices are destroyed. If elements are added, suitable
devices are created.
Applications should monitor the system for sessions and hardware devices.
For each session they want to operate on, they create an idev_session
object and add hardware to that object. The idev interface requires the
application to monitor the system (preferably via sysview_*, but not
required) for hardware devices. Whenever hardware is added to the idev
session, new devices *might* be created. The relationship between hardware
and high-level idev-devices is hidden in the idev-session and not exposed.
Internally, the idev elements and devices are virtual objects. Each real
hardware and device type inherits those virtual objects and provides real
elements and devices. Those types will be added in follow-up commits.
Data flow from hardware to the application is done via idev_*_feed()
functions. Data flow from applications to hardware is done via
idev_*_feedback() functions. Feedback is usually used for LEDs, FF and
similar operations.
We're going to need multiple binaries that provide session-services via
logind device management. To avoid re-writing the seat/session/device
scan/monitor interface for each of them, this commit adds a generic helper
to libsystemd-terminal:
The sysview interface scans and tracks seats, sessions and devices on a
system. It basically mirrors the state of logind on the application side.
Now, each session-service can listen for matching sessions and
attach to them. On each session, managed device access is provided. This
way, it is pretty simple to write session-services that attach to multiple
sessions (even split across seats).
hibernate-resume-generator understands resume= kernel command line parameter
and instantiates the systemd-resume@.service accordingly if it is passed.
This enables resume from hibernation using device specified on the kernel
command line, and it may be specified either as "/dev/disk/by-foo/bar"
or "FOO=bar", not only "/dev/sdXY" which is understood by the in-kernel
implementation.
So now resume= is brought on par with root= in terms of possible ways to
specify a device.
This can be used to initiate a resume from hibernation by path to a swap
device containing the hibernation image.
The respective templated unit is also added. It is instantiated using
path to the desired resume device.
When this system-wide start-up timeout is hit we execute one of the
failure actions already implemented for services that fail.
This should not only be useful on embedded devices, but also on laptops
which have the power-button reachable when the lid is closed. This
devices, when in a backpack might get powered on by accident due to the
easily reachable power button. We want to make sure that the system
turns itself off if it starts up due this after a while.
When the system manages to fully start-up logind will suspend the
machine by default if the lid is closed. However, in some cases we don't
even get as far as logind, and the boot hangs much earlier, for example
because we ask for a LUKS password that nobody ever enters.
Yeah, this is a real-life problem on my Yoga 13, which has one of those
easily accessible power buttons, even if the device is closed.
In contrast to the DHCP/IPv4LL/ICMP6 APIs sd-network is not a protocol
implementation but a client API for networkd, hence move it into
libsystemd proper.
In the long run this should become a full fledged client to networkd
(but not before networkd learns bus support). For now, just pull
interesting data out of networkd, udev, and rtnl and present it to the
user, in a simple but useful output.
We are unlikely to evert support most of them, but we can at least
display the types properly.
The list is taken from the IANA list.
The table of number->name mappings is converted to a switch
statement. gcc does a nice job of optimizing lookup (when optimization
is enabled).
systemd-resolve-host -t is now case insensitive.
We now maintain two lists of DNS servers: system servers and fallback
servers.
system servers are used in combination with any per-link servers.
fallback servers are only used if there are no system servers or
per-link servers configured.
The system server list is supposed to be populated from a foreign tool's
/etc/resolv.conf (not implemented yet).
Also adds a configuration switch for LLMNR, that allows configuring
whether LLMNR shall be used simply for resolving or also for responding.
Make sure we format UTF-8 labels as IDNA when writing them to DNS
packets, and as native UTF-8 when writing them to mDNS or LLMNR packets.
When comparing or processing labels always consider native UTF-8 and
IDNA formats equivalent.
LOC records have a version field. So far only version 0 has been
published, but if a record with a different version was encountered,
our only recourse is to treat it as an unknown type. This is
implemented with the 'unparseable' flag, which causes the
serialization/deserialization and printing function to cause the
record as a blob. The flag can be used if other packet types cannot be
parsed for whatever reason.
This tool will warn about misspelt directives, unknown sections, and
non-executable commands. It will also catch the common mistake of
using Accept=yes with a non-template unit and vice versa.
https://bugs.freedesktop.org/show_bug.cgi?id=56607
Commit 637f421e5c ("cgroups: always propagate controller membership
to siblings") changed the mask propagation logic, but the test wasn't
updated.
Move to normal tests from manual tests, it should not touch the system
anymore.
Also add a bit of debugging output to help diagnose problems,
add missing units, and simplify cppflags.
Move test-engine to normal tests from manual tests, it should now
work without destroying the system.
Our version has evolved independently of the original table
in systemd-config-keyboard, so it cannot be ever regenerated from
original upstream. Remove script to avoid confusion.
The unifont layer of libsystemd-terminal provides a fallback font for
situations where no system-fonts are available, or if you don't want to
deal with traditional font-formats for some reasons.
The unifont API mmaps a pre-compiled bitmap font that was generated out of
GNU-Unifont font-data. This guarantees, that all users of the font will
share the pages in memory. Furthermore, the layout of the binary file
allows accessing glyph data in O(1) without pre-rendering glyphs etc. That
is, the OS can skip loading pages for glyphs that we never access.
Note that this is currently a test-run and we want to include the binary
file in the GNU-Unifont package. However, until it was considered stable
and accepted by the maintainers, we will ship it as part of systemd. So
far it's only enabled with the experimental --enable-terminal, anyway.
The systemd-subterm example is a stacked terminal that shows how to
use sd-term. Instead of rendering images and displaying it via X11/etc.,
it uses its parent terminal to display the page (terminal-emulator inside
a terminal-emulator) (like GNU-screen and friends do).
This is only for testing and not installed system-wide!
The screen-layer represents the terminal-side (compared to the host-side).
It connects term_parser with term_page and implements all the required
control sequences.
We do not implement all available control sequences. Even though our
parser recognizes them, there is no need to handle them. Most of them are
legacy or unused. We try to be as compatible to xterm, so if we missed
something, we can implement it later. However, all the VT510 / VT440 stuff
can safely be skipped (who needs terminal macros? WTF?).
The keyboard-handling is still missing. It will be added once
systemd-console is available and we pulled in the key-definitions.
The term-parser is used to parse any input from TTY-clients. It reads CSI,
DCS, OSC and ST control sequences and normal escape sequences. It doesn't
do anything with the parsed data besides detecting the sequence and
returning it. The caller has to react to them.
The parser also comes with its own UTF-8 helpers. The reason for that is
that we don't want to assert() or hard-fail on parsing errors. Instead,
we treat any invalid UTF-8 sequences as ISO-8859-1. This allows pasting
invalid data into a terminal (which cannot be controlled through the TTY,
anyway) and we still deal with it in a proper manner.
This is _required_ for 8-bit and 7-bit DEC modes (including the g0-g3
mappings), so it's not just an ugly fallback because we can (it's still
horribly ugly but at least we have an excuse).
Rather than refetching the link information on ever event, we liston to
rtnl to track them. Much code stolen from resolved.
This will allow us to simplify the sd-network api and don't expose
information available over rtnl.
This commit introduces libsystemd-ui, a systemd-internal helper library
that will contain all the UI related functionality. It is going to be used
by systemd-welcomed, systemd-consoled, systemd-greeter and systemd-er.
Further use-cases may follow.
For now, this commit only adds terminal-page handling based on lines only.
Follow-up commits will add more functionality.
This Pty API wraps the ugliness that is POSIX PTY. It takes care of:
- edge-triggered HUP handling (avoid heavy CPU-usage on vhangup)
- HUP vs. input-queue draining (handle HUP _after_ draining the whole
input queue)
- SIGCHLD vs. HUP (HUP is no reliable way to catch PTY deaths, always
use SIGCHLD. Otherwise, vhangup() and friends will break.)
- Output queue buffering (async EPOLLOUT handling)
- synchronous setup (via Barrier API)
At the same time, the PTY API does not execve(). It simply fork()s and
leaves everything else to the caller. Usually, they execve() but we
support other setups, too.
This will be needed by multiple UI binaries (systemd-console, systemd-er,
...) so it's placed in src/shared/. It's not strictly related to
libsystemd-terminal, so it's not included there.
The Barrier-API simplifies cross-fork() synchronization a lot. Replace the
hard-coded eventfd-util implementation and drop it.
Compared to the old API, Barriers also handle exit() of the remote side as
abortion. This way, segfaults will not cause the parent to deadlock.
EINTR handling is currently ignored for any barrier-waits. This can easily
be added, but it isn't needed so far so I dropped it. EINTR handling in
general is ugly, anyway. You need to deal with pselect/ppoll/... variants
and make sure not to unblock signals at the wrong times. So genrally,
there's little use in adding it.
The "Barrier" object is a simple inter-process barrier implementation. It
allows placing synchronization points and waiting for the other side to
reach it. Additionally, it has an abortion-mechanism as second-layer
synchronization to send abortion-events asynchronously to the other side.
The API is usually used to synchronize processes during fork(). However,
it can be extended to pass state through execve() so you could synchronize
beyond execve().
Usually, it's used like this (error-handling replaced by assert() for
simplicity):
Barrier b;
r = barrier_init(&b);
assert_se(r >= 0);
pid = fork();
assert_se(pid >= 0);
if (pid == 0) {
barrier_set_role(&b, BARRIER_CHILD);
...do child post-setup...
if (CHILD_SETUP_FAILED)
exit(1);
...child setup done...
barrier_place(&b);
if (!barrier_sync(&b)) {
/* parent setup failed */
exit(1);
}
barrier_destroy(&b); /* redundant as execve() and exit() imply this */
/* parent & child setup successful */
execve(...);
}
barrier_set_role(&b, BARRIER_PARENT);
...do parent post-setup...
if (PARENT_SETUP_FAILED) {
barrier_abort(&b); /* send abortion event */
barrier_wait_abortion(&b); /* wait for child to abort (exit() implies abortion) */
barrier_destroy(&b);
...bail out...
}
...parent setup done...
barrier_place(&b);
if (!barrier_sync(&b)) {
...child setup failed... ;
barrier_destroy(&b);
...bail out...
}
barrier_destroy(&b);
...child setup successfull...
This is the most basic API. Using barrier_place() to place barriers and
barrier_sync() to perform a full synchronization between both processes.
barrier_abort() places an abortion barrier which superceeds any other
barriers, exit() (or barrier_destroy()) places an abortion-barrier that
queues behind existing barriers (thus *not* replacing existing barriers
unlike barrier_abort()).
This example uses hard-synchronization with wait_abortion(), sync() and
friends. These are all optional. Barriers are highly dynamic and can be
used for one-way synchronization or even no synchronization at all
(postponing it for later). The sync() call performs a full two-way
synchronization.
The API is documented and should be fairly self-explanatory. A test-suite
shows some special semantics regarding abortion, wait_next() and exit().
Internally, barriers use two eventfds and a pipe. The pipe is used to
detect exit()s of the remote side as eventfds do not allow that. The
eventfds are used to place barriers, one for each side. Barriers itself
are numbered, but the numbers are reused once both sides reached the same
barrier, thus you cannot address barriers by the index. Moreover, the
numbering is implicit and we only store a counter. This makes the
implementation itself very lightweight, which is probably negligible
considering that we need 3 FDs for a barrier..
Last but not least: This barrier implementation is quite heavy. It's
definitely not meant for fast IPC synchronization. However, it's very easy
to use. And given the *HUGE* overhead of fork(), the barrier-overhead
should be negligible.
Directory src/journal has become one of the largest directories,
and since systemd-journal-gatewayd, systemd-journal-remote, and
forthcoming systemd-journal-upload are all closely related, create
a separate directory for them.
Let's turn resolved into a something truly useful: a fully asynchronous
DNS stub resolver that subscribes to network changes.
(More to come: caching, LLMNR, mDNS/DNS-SD, DNSSEC, IDN, NSS module)
It is already in nodist_systemunit_DATA and if it is
shipped, it contains the hardcoded path to systemctl
which will cause it to fail to start when
rootprefix != prefix and rootbindir != bindir.
This reverts commit 0c26bfc3d2.
src/core/org.freedesktop.systemd1.policy.in.in depends on values which
are specified at configure time, so we cannot ship the corresponding
policy file in the tarball.
Since we need to regenerate one policy file, we might as well generate
them all.
The systemd-escape utility might be used during early boot (e.g. when
being triggered from udev rules), so move it to rootbindir to support
systems with a split /usr setup.
This patch adds supports networkd to configure bond mode
during creation via persistent conf. Mode can be configured
with conf param 'Mode'. A new section Bond is added to the
conf to support bond mode.
These modes can be configured now.
balance-rr
active-backup
balance-xor
broadcast
802.3ad
balance-tlb
balance-alb
Example conf file: test-bond.conf
[NetDev]
Name=bond1
Kind=bond
[Bond]
Mode=balance-xor
Test case:
1. start networkd service:
12: bond1: <BROADCAST,MULTICAST,MASTER,UP,LOWER_UP> mtu 1500 qdisc
noqueue state UNKNOWN mode DEFAULT group default
link/ether 22:89:6c:47:23:d2 brd ff:ff:ff:ff:ff:ff
2. find bond mode:
cat /proc/net/bonding/bond1
Ethernet Channel Bonding Driver: v3.7.1 (April 27, 2011)
Bonding Mode: load balancing (xor)
Transmit Hash Policy: layer2 (0)
MII Status: up
MII Polling Interval (ms): 0
Up Delay (ms): 0
Down Delay (ms): 0
Changes:
1. Added file networkd-bond.c
2. Bond mode enum BondMode
3. conf section [Bond]
[tomegun: whitespace]
As Zbigniew pointed out a new ConditionFirstBoot= appears like the nicer
way to hook in systemd-firstboot.service on first boots (those with /etc
unpopulated), so let's do this, and get rid of the generator again.
A new tool "systemd-firstboot" can be used either interactively on boot,
where it will query basic locale, timezone, hostname, root password
information and set it. Or it can be used non-interactively from the
command line when prepareing disk images for booting. When used
non-inertactively the tool can either copy settings from the host, or
take settings on the command line.
$ systemd-firstboot --root=/path/to/my/new/root --copy-locale --copy-root-password --hostname=waldi
The tool will be automatically invoked (interactively) now on first boot
if /etc is found unpopulated.
This also creates the infrastructure for generators to be notified via
an environment variable whether they are running on the first boot, or
not.
This is useful to test the behaviour of the compressor for various buffer
sizes.
Time is limited to a minute per compression, since otherwise, when LZ4
takes more than a second which is necessary to reduce the noise, XZ
takes more than 10 minutes.
% build/test-compress-benchmark (without time limit)
XZ: compressed & decompressed 2535300963 bytes in 794.57s (3.04MiB/s), mean compresion 99.95%, skipped 3570 bytes
LZ4: compressed & decompressed 2535303543 bytes in 1.56s (1550.07MiB/s), mean compresion 99.60%, skipped 990 bytes
% build/test-compress-benchmark (with time limit)
XZ: compressed & decompressed 174321481 bytes in 60.02s (2.77MiB/s), mean compresion 99.76%, skipped 3570 bytes
LZ4: compressed & decompressed 2535303543 bytes in 1.63s (1480.83MiB/s), mean compresion 99.60%, skipped 990 bytes
It appears that there's a bug in lzma_end where it leaks 32 bytes.
Add liblz4 as an optional dependency when requested with --enable-lz4,
and use it in preference to liblzma for journal blob and coredump
compression. To retain backwards compatibility, XZ is used to
decompress old blobs.
Things will function correctly only with lz4-119.
Based on the benchmarks found on the web, lz4 seems to be the best
choice for "quick" compressors atm.
For pkg-config status, see http://code.google.com/p/lz4/issues/detail?id=135.
This patch introduces TUN/TAP device creation support
to networkd.
Example conf to create a tap device:
file: tap.netdev
------------------
[NetDev]
Name=tap-test
Kind=tap
[Tap]
OneQueue=true
MultiQueue=true
PacketInfo=true
User=sus
Group=sus
------------------
Test:
1. output of ip link
tap-test: tap pi one_queue UNKNOWN_FLAGS:900 user 1000 group 1000
id:
uid=1000(sus) gid=10(wheel) groups=10(wheel),1000(sus)
context=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023
Modifications:
Added:
1. file networkd-tuntap.c
3. netdev kind NETDEV_KIND_TUN and NETDEV_KIND_TAP
2. Tun and Tap Sections and config params to parse
conf and gperf conf parameters
[tomegun: tweak the 'kind' checking for received ifindex]
This new tool is based on "sd-path", a new (so far unexported) API for
libsystemd, that can hopefully grow into a workable API covering /opt
and more one day.
Instead of adjusting job timeouts in the core, let fstab-generator
write out a dropin snippet with the appropriate JobTimeout.
x-systemd-device.timeout option is removed from Options= line
in the generated unit.
The functions to write dropins are moved from core/unit.c to
shared/dropin.c, to make them available outside of core.
generator.c is moved to libsystemd-label, because it now uses
functions defined in dropin.c, which are in libsystemd-label.
When disk space taken up by coredumps grows beyond a configured limit
start removing the oldest coredump of the user with the most coredumps,
until we get below the limit again.
So that building from an archive works even if intltool is not present.
The README file already mentioned that intltool should only be required
when building from git.
Tested: Built it from the distribution archive on a host without intltool.
$ ./configure --enable-polkit
$ make
Running "make dist" requires --enable-compat-libs since DIST_SOURCES will list
generated files such as libsystemd-daemon.c.
Tested:
$ ./configure && make && make dist
*** compat-libs must be enabled in order to make dist
make: *** [dist-check-compat-libs] Error 1
Running "make dist" requires Python support since some of the man page sources
(such as man/systemd.index.xml and man/systemd.directives.xml) are generated by
Python scripts, so break "make dist" and give an useful error message when
Python or the Python lxml module is not available.
Tested:
$ ./configure --without-python && make && make dist
*** python and python-lxml module must be installed and enabled in order to make dist
make: *** [dist-check-python] Error 1
Python support is pretty much essential to create man pages, so we should make
sure that distcheck will request it during configure.
Tested: Successfully ran "make distcheck" and confirmed --with-python was
present in the ./configure run inside the unpacked distribution directory.
File src/python-systemd/id128-constants.h is auto generated and its generation
does not require special tools, only sed. There is no point in bundling it in
the distribution archive, so let's mark it as nodist_ to have it excluded.
Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=80006
Tested: Successfully ran "make dist" after ./configure --without-python.
The sysusers.d/systemd.conf configuration file was originally introduced in
commit 1b99214789, but it was not marked for cleanup. This caused distcheck
to complain about the file not being removed by distcleam.
Tested: Successfully ran "make distcheck" with this patchset.
It was incorrectly looking for a file in src/libsystemd-network/ when the file was actually deployed to src/systemd/ instead. This broke "make dist".
Tested: "make dist" works again after this patchset is applied.
Fixes: f20a35cc0d
Makefile.am had a reference to it but it none of the sources included it.
Tested: "make dist" works again after this patchset is applied.
Fixes: 2ea8857eff
debug-generator can mask specific units if they are specified on the
kernel command line with systemd.mask=.
debug-generator can pull in debug-shell.service is systemd.debug-shell
is passed on the kernel command line.
Create a structure describing a DHCPv6 lease. Add internal functions
for creating a new lease and accessing the server ID, preference and
IAID. Provide functions for clearing addresses and associated timers.
External users are initially given only the capabilities of
referencing and unreferencing the lease structure.
Verify the Solicit message created by the DHCPv6 client code.
Provide local variants for detect_vm(), detect_container() and
detect_virtualization() defined in virt.h. This makes the DHCPv6
library believe it is run in a container and does not try to request
interface information from udev for the non-existing interface index
used by the test case code.
Add option appending and parsing. DHCPv6 options are not aligned, thus
the option handling code must be able to handle options starting at
any byte boundary.
Add a test case for the basic option handling.
Feed a Router Advertisement to the code and expect proper events
each time. The sending part is ignored, as all of it is static code
in the real dhcp_network_icmp6_send_rs() function.
Provide functions to bind the ICMPv6 socket to the approriate interface
and set multicast sending and receiving according to RFC 3493, section
5.2. and RFC 3542, sections 3. and 3.3. Filter out all ICMPv6 messages
except Router Advertisements for the socket in question according to
RFC 3542, section 3.2.
Send Router Solicitations to the all routers multicast group as
described in RFC 4861, section 6. and act on the received Router
Advertisments according to section 6.3.7.
Implement a similar API for ICMPv6 handling as is done for DHCPv4 and
DHCPv6.
