Apart from the 16 virtual terminals, Syscons allocates two device nodes
that should not really be TTYs, even though they are. One of them is
consolectl. In RELENG_7 and before, these device nodes are used in
single user mode. After I simplified input path, we only use this device
node to call ioctl() on (moused, Xorg, vidcontrol).
When you call ioctl() on consolectl, it will behave the same as being
called on the first window.
After I imported libteken into the source tree, I noticed syscons didn't
store the cursor position inside the terminal emulator, but inside the
virtual terminal stat. This is not very useful, because when you
implement more complex forms of line wrapping, you need to keep track of
more state than just the cursor position.
Because the kernel messages didn't share the same terminal emulator as
ttyv0, this caused a lot of strange things, like kernel messages being
misplaced and a missing notification to resize the terminal emulator for
kernel messages never to be resized when using vidcontrol.
This patch just removes kernel_console_ts and adds a special parameter
to te_puts to determine whether messages should be printed using regular
colors or the ones for kernel messages.
Reported by: ache
Tested by: nyan, garga (older version)
We should just leave the underlying TTY objects alone when scrolling
around in KDB. It should be handled by Syscons exclusively.
Reported by: pluknet gmail com
Some time ago I started working on a library called libteken, which is
terminal emulator. It does not buffer any screen contents, but only
keeps terminal state, such as cursor position, attributes, etc. It
should implement all escape sequences that are implemented by the
cons25 terminal emulator, but also a fair amount of sequences that are
present in VT100 and xterm.
A lot of random notes, which could be of interest to users/developers:
- Even though I'm leaving the terminal type set to `cons25', users can
do experiments with placing `xterm-color' in /etc/ttys. Because we
only implement a subset of features of xterm, this may cause
artifacts. We should consider extending libteken, because in my
opinion xterm is the way to go. Some missing features:
- Keypad application mode (DECKPAM)
- Character sets (SCS)
- libteken is filled with a fair amount of assertions, but unfortunately
we cannot go into the debugger anymore if we fail them. I've done
development of this library almost entirely in userspace. In
sys/dev/syscons/teken there are two applications that can be helpful
when debugging the code:
- teken_demo: a terminal emulator that can be started from a regular
xterm that emulates a terminal using libteken. This application can
be very useful to debug any rendering issues.
- teken_stress: a stress testing application that emulates random
terminal output. libteken has literally survived multiple terabytes
of random input.
- libteken also includes support for UTF-8, but unfortunately our input
layer and font renderer don't support this. If users want to
experiment with UTF-8 support, they can enable `TEKEN_UTF8' in
teken.h. If you recompile your kernel or the teken_demo application,
you can hold some nice experiments.
- I've left PC98 the way it is right now. The PC98 platform has a custom
syscons renderer, which supports some form of localised input. Maybe
we should port PC98 to libteken by the time syscons supports UTF-8?
- I've removed the `dumb' terminal emulator. It has been broken for
years. It hasn't survived the `struct proc' -> `struct thread'
conversion.
- To prevent confusion among people that want to hack on libteken:
unlike syscons, the state machines that parse the escape sequences are
machine generated. This means that if you want to add new escape
sequences, you have to add an entry to the `sequences' file. This will
cause new entries to be added to `teken_state.h'.
- Any rendering artifacts that didn't occur prior to this commit are by
accident. They should be reported to me, so I can fix them.
Discussed on: current@, hackers@
Discussed with: philip (at 25C3)
The syscons code disabled scroll lock inside sc_cnputs() if it's going
to print a system message. The code currently wants to process any TTY
output data as well, but we cannot do this, because the TTY lock is a
sleep mutex, while cnputs() picks up a spin mutex.
Disable the code for now. It solves a panic when a console message is
printed while scroll lock is enabled. One solution would be to
initialize a task structure here.
Reported by: Paul B. Mahol <onemda gmail com>
When I was hacking on uart(4) to make it work with the MPSAFE TTY layer,
I noticed there was a difference between the way syscons and uart work
with respect to consoles:
- The uart(4) driver sets cn_name to the corresponding ttyu%r node,
which means init(8) (which opens /dev/console) will have its output
redirected to /dev/ttyu%r. After /etc/rc is done, it can spawn a getty
on that device node as well.
- Syscons used a little different approach. Apart from the /dev/ttyv%r
nodes, it creates a /dev/consolectl node. This device node is used by
moused and others to deliver their data, but for some reason it also
acts as a TTY, which shares its stat structure with ttyv0. This device
node is used as a console (run conscontrol).
There are a couple advantages of this approach:
- Because we use two different TTY's to represent the 0th syscons
window, we allocate two sets of TTY buffers. Even if you don't use
/dev/consolectl after the system has booted (systems that don't run
moused), it seems the buffers are still allocated.
- We have to apply an evil hack to redirect input to /dev/consolectl.
Because each window (stat) is associated not associated with one TTY,
syscons solves this by redirecting all input to closed TTY's to
consolectl.
This means that opening /dev/ttyv0 while in single user mode will
probably cause strange things to happen with respect to keyboard input
redirection.
The first patch that I discussed with philip@ turned consolectl into a
symlink to ttyv0, but this was not a good idea, because in theory we
would want consolectl to be a simple device node, which contains all the
`privileged' ioctl()'s. Apart from that, it didn't work, because each
time /dev/ttyv0 got revoked, moused also lost its descriptor to deliver
input, which meant you had to plug out/in your mouse to make it work
again. This version just leaves the consolectl device the way it is. It
can still be used to write output to ttyv0, but it can no longer receive
any input.
In my opinion this patch is not a complete solution, but it's already a
step in the good direction. It would allow us to turn consolectl into a
special (non-TTY) device node in the far future. It shaves off 15 KB of
wasted TTY buffer space.
Discussed with: philip
The last half year I've been working on a replacement TTY layer for the
FreeBSD kernel. The new TTY layer was designed to improve the following:
- Improved driver model:
The old TTY layer has a driver model that is not abstract enough to
make it friendly to use. A good example is the output path, where the
device drivers directly access the output buffers. This means that an
in-kernel PPP implementation must always convert network buffers into
TTY buffers.
If a PPP implementation would be built on top of the new TTY layer
(still needs a hooks layer, though), it would allow the PPP
implementation to directly hand the data to the TTY driver.
- Improved hotplugging:
With the old TTY layer, it isn't entirely safe to destroy TTY's from
the system. This implementation has a two-step destructing design,
where the driver first abandons the TTY. After all threads have left
the TTY, the TTY layer calls a routine in the driver, which can be
used to free resources (unit numbers, etc).
The pts(4) driver also implements this feature, which means
posix_openpt() will now return PTY's that are created on the fly.
- Improved performance:
One of the major improvements is the per-TTY mutex, which is expected
to improve scalability when compared to the old Giant locking.
Another change is the unbuffered copying to userspace, which is both
used on TTY device nodes and PTY masters.
Upgrading should be quite straightforward. Unlike previous versions,
existing kernel configuration files do not need to be changed, except
when they reference device drivers that are listed in UPDATING.
Obtained from: //depot/projects/mpsafetty/...
Approved by: philip (ex-mentor)
Discussed: on the lists, at BSDCan, at the DevSummit
Sponsored by: Snow B.V., the Netherlands
dcons(4) fixed by: kan
PZERO + 1. The sleeping process at the priority <= PZERO is counted as
blocked, or, as comment states, 'disk wait'. PZERO + 1 works as well,
and does not cause user confusion.
Reported by: sam <samflanker at gmail com>
MFC after: 1 week
these days, so de-generalize the acquire_timer/release_timer api
to just deal with speakers.
The new (optional) MD functions are:
timer_spkr_acquire()
timer_spkr_release()
and
timer_spkr_setfreq()
the last of which configures the timer to generate a tone of a given
frequency, in Hz instead of 1/1193182th of seconds.
Drop entirely timer2 on pc98, it is not used anywhere at all.
Move sysbeep() to kern/tty_cons.c and use the timer_spkr*() if
they exist, and do nothing otherwise.
Remove prototypes and empty acquire-/release-timer() and sysbeep()
functions from the non-beeping archs.
This eliminate the need for the speaker driver to know about
i8254frequency at all. In theory this makes the speaker driver MI,
contingent on the timer_spkr_*() functions existing but the driver
does not know this yet and still attaches to the ISA bus.
Syscons is more tricky, in one function, sc_tone(), it knows the hz
and things are just fine.
In the other function, sc_bell() it seems to get the period from
the KDMKTONE ioctl in terms if 1/1193182th second, so we hardcode
the 1193182 and leave it at that. It's probably not important.
Change a few other sysbeep() uses which obviously knew that the
argument was in terms of i8254 frequency, and leave alone those
that look like people thought sysbeep() took frequency in hertz.
This eliminates the knowledge of i8254_freq from all but the actual
clock.c code and the prof_machdep.c on amd64 and i386, where I think
it would be smart to ask for help from the timecounters anyway [TBD].
implemented with macros. This patch improves code readability. Reasoning
behind vidd_* is a sort of "video discipline".
List of macros is supposed to be complete--all methods of video_switch
ought to have their respective macros from now on.
Functionally, this code should be no-op. My intention is to leave current
behaviour of touched code as is.
No objections: rwatson
Silence on: freebsd-current@
Approved by: cognet
implemented with macros. This patch improves code readability. Reasoning
behind kbdd_* is a "keyboard discipline".
List of macros is supposed to be complete--all methods of keyboard_switch
should have their respective macros from now on.
Functionally, this code should be no-op. My intention is to leave current
behaviour of code as is.
Glanced at by: rwatson
Reviewed by: emax, marcel
Approved by: cognet
for that argument. This will allow DDB to detect the broad category of
reason why the debugger has been entered, which it can use for the
purposes of deciding which DDB script to run.
Assign approximate why values to all current consumers of the
kdb_enter() interface.
- The output routine of low level console is not protected by any lock
by default.
- Increment and decrement of sc->write_in_progress are not atomic and
this may cause console hang.
- We also have many other states used by emulator that should be protected
by the lock.
- This change does not fix interspersed messages which PRINTF_BUFR_SIZE
kernel option should fix.
Approved by: re (bmah)
MFC after: 1 week
to become unkillable when that process is sent a termination signal. The
process will sit in waitvt looping in the kernel, and chewing up all
available CPU until the system is rebooted.
Submitted by: Jilles Tjoelker <jilles@stack.nl>
Reviewed by: bde
Approved by: re (kensmith)
MFC after: 1 week
to be switched to is saved in sc->delayed_next_scr and
the actual switch is performed later. It was possible
to get into the endless loop when attempting to switch
to a closed vty (which is not allowed and beep-alerted
when attempted) and when the visual beep was in effect.
This caused sc->delayed_next_scr to never be reset and
endless attempts to switch to a closed vty and endless
visual beeping. How to repeat:
- boot into single-user
- run "kbdcontrol -b visual"
- quickly press Alt+F2 two times
PR: kern/68016
X-MFC after: 6.2-RELEASE
specific privilege names to a broad range of privileges. These may
require some future tweaking.
Sponsored by: nCircle Network Security, Inc.
Obtained from: TrustedBSD Project
Discussed on: arch@
Reviewed (at least in part) by: mlaier, jmg, pjd, bde, ceri,
Alex Lyashkov <umka at sevcity dot net>,
Skip Ford <skip dot ford at verizon dot net>,
Antoine Brodin <antoine dot brodin at laposte dot net>
ioctls passing integer arguments should use the _IOWINT() macro.
This fixes a lot of ioctl's not working on sparc64, most notable
being keyboard/syscons ioctls.
Full ABI compatibility is provided, with the bonus of fixing the
handling of old ioctls on sparc64.
Reviewed by: bde (with contributions)
Tested by: emax, marius
MFC after: 1 week
in syscons. This replaces a simple access semaphore that was assumed to be
protected by Giant but often was not. If two threads that were otherwise
SMP-safe called printf at the same time, there was a high likelyhood that
the semaphore would get corrupted and result in a permanently frozen video
console. This is similar to what is already done in the serial console
drivers.
This used to make syscons switch to vty0 when we entered DDB but this
was lost in the KDB shuffle. We may want to bring it back down the road
but it should be done by calling cn_init_t/cn_term_t instead, possibly
with a flag argument saying "Debugger!"
was not checked at all. There is only one case when sc_clean_up()
can fail, because of wait_scrn_saver_stop(), but it doesn't hurt
to check anyway.
Reviewed by: rodrigc
Found by: Coverity Prevent
By default syscons(4) will look for the kbdmux(4) keyboard first, and then,
if not found, look for any keyboard.
Current kbd code is modified so if kbdmux(4) is the current keyboard, all
new keyboards are automatically added to the kbdmux(4).
Switch to kbdmux(4) can be done at boot time, by loading kbdmux module at
the loader prompt, or at runtime, by kldload'ing the kbdmux module and
releasing current active keyboard.
If, for whatever reason, kbdmux(4) is not required/desired then just do
not load it and everything should work as before. It is also possible to
kldunload kbdmux at runtime and syscons(4) will automatically switch to
the first available keyboard.
No response from: freebsd-current@
MFC after: 1 day
same behavior to be controlled by the sysctls, hw.syscons.kbd_kbdkey
and hw.syscons.kbd_reboot respectively.
Apologies to the submitter for taking so long to commit this simple
change.
PR: kern/72728
Submitted by: Luca Morettoni <morettoni at libero dot it>
MFC After: 3 days
and do some preparations for handling 12x22 fonts (currently lots of code
implies and/or hardcodes a font width of 8 pixels). This will be required
on sparc64 which uses a default font size of 12x22 in order to add font
loading and saving support as well as to use a syscons(4)-supplied mouse
pointer image.
This API breakage is committed now so it can be MFC'ed in time for 6.0
and later on upcoming framebuffer drivers destined for use on sparc64
and which are expected to rely on using font loading internally and on
a syscons(4)-supplied mouse pointer image can be easily MFC'ed to
RELENG_6 rather than requiring a backport.
Tested on: i386, sparc64, make universe
MFC after: 1 week
by explicitly setting sc->font_width, in the same
places where sc->font_size is set, instead of
relying on the default initialized value of 0 for sc->font_width.
PR: kern/84836
Reported by: Andrey V. Elsukov <bu7cher at yandex dot ru>
MFC after: 2 days
o Add two new ioctl's KBADDKBD and KBRELKBD. These are used to add and remove
keyboard to (and from) kbdmux(4) keyboard multiplexer;
o Introduce new kbd_find_keyboard2() function. It does exactly the same job
as kbd_find_keyboard() function except it allows to specify starting index.
This function can be used to iterate over keyboards array;
o Re-implement kbd_find_keyboard() as call to kbd_find_keyboard2() with starting
index of zero;
o Make sure syscons(4) passed KBADDKBD and KBRELKBD ioctl's onto currently
active keyboard.
These changes should not have any visible effect.
MFC after: 1 week
24, and 32 bit modes. To use that, syscons(4) must be built with
the compile time option 'options SC_PIXEL_MODE', and VESA support (a.k.a.
vesa.ko) must be either loaded, or be compiled into the kernel.
Do not return EINVAL when the mouse state is changed to what it already is,
which seems to cause problems when you have two mice attached, and
applications are not likely obtain useful information through the EINVAL
caused by showing the mouse pointer twice.
Teach vidcontrol(8) about mode names like MODE_<NUMBER>, where <NUMBER> is
the video mode number from the vidcontrol -i mode output. Also, revert the
video mode if something fails.
Obtained from: DragonFlyBSD
Discussed at: current@ with patch attached [1]
PR: kern/71142 [2]
Submitted by: Xuefeng DENG <dsnofe at msn com> [1],
Cyrille Lefevre <cyrille dot lefevre at laposte dot net> [2]
uses white) so base the color of the border on SC_NORM_ATTR rather
than hardcoding BG_BLACK.
- Use SC_DRIVER_NAME rather than hardcoding 'sc' in message strings
(see also sys/dev/syscons/syscons.h rev. 1.82).
modes on a tty structure.
Both the ".init" and the current settings are initialized allowing
the function to be used both at attach and open time.
The function takes an argument to decide if echoing should be enabled.
Echoing should not be enabled for regular physical serial ports
unless they are consoles, in which case they should be configured
by ttyconsolemode() instead.
Use the new function throughout.
want a splash screen.
There seems to be some confusion in the syscons code as to the meaning of
the SC_KERNEL_CONSOLE flag. Its absence is sometimes interpreted to mean
"I am not the system console", and sometimes to mean "I am not the only
VGA console" (see the font loading code for an example of the latter).
Someone with better syscons fu than myself should take a closer look.
future:
rename ttyopen() -> tty_open() and ttyclose() -> tty_close().
We need the ttyopen() and ttyclose() for the new generic cdevsw
functions for tty devices in order to have consistent naming.
it's in the way even more. Basicly: remove all alpha specific console
support from gfb(4), sio(4) and syscons(4). Rewrite the alpha console
initialization to be identical to all other platforms. In a nutshell:
call cninit().
The platform specific code now only sets or clears RB_SERIAL and thus
automaticly causes the right console to be selected.
sio.c:
o Replace the remote GDB hacks and use the GDB debug port interface
instead.
o Make debugging code conditional upon KDB instead of DDB.
o Call kdb_alt_break() instead of db_alt_break().
o Call kdb_enter() instead of breakpoint().
o Remove the ugly compatibility of using the console as the debug
port.
The big lines are:
NODEV -> NULL
NOUDEV -> NODEV
udev_t -> dev_t
udev2dev() -> findcdev()
Various minor adjustments including handling of userland access to kernel
space struct cdev etc.
