event handler, dev_clone, which accepts a credential argument.
Implementors of the event can ignore it if they're not interested,
and most do. This avoids having multiple event handler types and
fall-back/precedence logic in devfs.
This changes the kernel API for /dev cloning, and may affect third
party packages containg cloning kernel modules.
Requested by: phk
MFC after: 3 days
null-modem tty device emulate the speed settings faithfully.
The speed is emulated independently for the two directions, using
the slower of the local sides ispeed and the remote sides ospeed.
The emulated speed takes settings of bits/char, parity and stopbit
into account.
Inspired by: The BSD-DK Editor Celebrity Deathmatch Contest
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.
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.
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.
It was based on the pty(4) driver which as a tty side an a non-tty side.
Nmdm(4) seems to have inherited two symmetric sides from pty but
unfortunately they are not quite ttys. Running a getty one one
side and tip on the other failed to produce NL->CRNL mapping for
instance.
Rip out the basically bogus cdevsw->{read,write} functions and rely
on ttyread() and ttywrite() which does the same thing.
Use taskqueue_swi_giant to run a task for either side to do what
needs to be done. (Direct calling is not an option as it leads to
recursion.) Trigger the task from the t_oproc and t_stop methods.
Default the ports to not ECHO. Since we neither rate limiting nor
emulation, two ports echoing each other is a really bad idea, which
can only be properly mitigated by rate limiting, rate emulation or
intelligent detection. Rate emulation would be a neat feature.
Ditch the modem-line emulation, if needed for some app, it needs
to be thought much more about how it interacts with the open/close
logic.
Introduce d_version field in struct cdevsw, this must always be
initialized to D_VERSION.
Flip sense of D_NOGIANT flag to D_NEEDGIANT, this involves removing
four D_NOGIANT flags and adding 145 D_NEEDGIANT flags.
Add missing D_TTY flags to various drivers.
Complete asserts that dev_t's passed to ttyread(), ttywrite(),
ttypoll() and ttykqwrite() have (d_flags & D_TTY) and a struct tty
pointer.
Make ttyread(), ttywrite(), ttypoll() and ttykqwrite() the default
cdevsw methods for D_TTY drivers and remove the explicit initializations
in various drivers cdevsw structures.
This commit adds a couple of functions for pseudodrivers to use for
implementing cloning in a manner we will be able to lock down (shortly).
Basically what happens is that pseudo drivers get a way to ask for
"give me the dev_t with this unit number" or alternatively "give
me a dev_t with the lowest guaranteed free unit number" (there is
unfortunately a lot of non-POLA in the exact numeric value of this
number, just live with it for now)
Managing the unit number space this way removes the need to use
rman(9) to do so in the drivers this greatly simplifies the code in
the drivers because even using rman(9) they still needed to manage
their dev_t's anyway.
I have taken the if_tun, if_tap, snp and nmdm drivers through the
mill, partly because they (ab)used makedev(), but mostly because
together they represent three different problems for device-cloning:
if_tun and snp is the plain case: just give me a device.
if_tap has two kinds of devices, with a flag for device type.
nmdm has paired devices (ala pty) can you can clone either of them.
thread being waken up. The thread waken up can run at a priority as
high as after tsleep().
- Replace selwakeup()s with selwakeuppri()s and pass appropriate
priorities.
- Add cv_broadcastpri() which raises the priority of the broadcast
threads. Used by selwakeuppri() if collision occurs.
Not objected in: -arch, -current
even could call VOP_REVOKE() on vnodes associated with its dev_t's
has originated, but it stops right here.
If there are things people belive destroy_dev() needs to learn how to
do, please tell me about it, preferably with a reproducible test case.
Include <sys/uio.h> in bluetooth code rather than rely on <sys/vnode.h>
to do so.
The fact that some of the USB code needs to include <sys/vnode.h>
still disturbs me greatly, but I do not have time to chase that.
branches:
Initialize struct cdevsw using C99 sparse initializtion and remove
all initializations to default values.
This patch is automatically generated and has been tested by compiling
LINT with all the fields in struct cdevsw in reverse order on alpha,
sparc64 and i386.
Approved by: re(scottl)
general cleanup of the API. The entire API now consists of two functions
similar to the pre-KSE API. The suser() function takes a thread pointer
as its only argument. The td_ucred member of this thread must be valid
so the only valid thread pointers are curthread and a few kernel threads
such as thread0. The suser_cred() function takes a pointer to a struct
ucred as its first argument and an integer flag as its second argument.
The flag is currently only used for the PRISON_ROOT flag.
Discussed on: smp@
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.
Sorry john! (your next MFC will be a doosie!)
Reviewed by: peter@freebsd.org, dillon@freebsd.org
X-MFC after: ha ha ha ha
CVSrepo deletion of the previous attempt will be requested:
--original message--
Add the 'virtual nulmodem driver'
Particularly useful for debuging kernels using vmware.
If your name is Bruce evans and you are a WIZ at tty interfaces,
then you should probably rip this to shreds and offer lots of suggestions and
patches. I've been using this since 4.0-CURRENT and it's never caused
problems but I'm sure I got something wrong. This is similar to the pty/cty
device driver except that both sides are ttys. Even minor numbers
are side A and odd minor numbers are side B.
Work needs to be done regarding what happens to the other side when you
close a node.
to use with vmware, configure vmware to redirect COM2 out to side A of one
of these and boot a kernel with teh gdb remote port set to sio1.
AFTER dropping into the gdb kernel debugger in your test kernel,
fire up gdb with it's remote port pointing at the appropriate side B.
To catch all console output, you can boot the vmware kernel with a serial
console, (COM1) similarly redirected to a nulmodem, and use 'tip' to observe it.
This is practically unaltered since pre 4.0 days except for
changes made along the way needed to make it compile, so any suggestions
or offers of total rewrites will be listenned to :-)
