Commit Graph

47 Commits

Author SHA1 Message Date
grehan
f30a88f9b1 Fix issue with nmdm and leading zeros in device name.
The nmdm code enforces a number between the 'nmdm' and 'A|B' portions
of the device name. This is then used as a unit number, and sprintf'd
back into the tty name. If leading zeros were used in the name,
the created device name is different than the string used for the
clone-open (e.g. /dev/nmdm0001A will result in /dev/nmdm1A).

Since unit numbers are no longer required with the updated tty
code, there seems to be no reason to force the string to be a
number. The fix is to allow an arbitrary string between
'nmdm' and 'A|B', within the constraints of devfs names. This allows
all existing user of numeric strings to continue to work, and also
allows more meaningful names to be used, such as bhyve VM names.

Tested on amd64, i386 and ppc64.

Reported by:	Dave Smith
PR:		192281
Reviewed by:	neel, glebius
Phabric:	D729
MFC after:	3 days
2014-09-10 05:44:15 +00:00
glebius
726ec729ea Make nmdm(4) destroy devices when both sides of a pair are disconnected.
This makes it possible to kldunload nmdm.ko when there are no users of it.

Reviewed by:	kib
Sponsored by:	Nginx, Inc.
2013-12-18 12:53:48 +00:00
ed
e97eae1577 Mark MALLOC_DEFINEs static that have no corresponding MALLOC_DECLAREs.
This means that their use is restricted to a single C file.
2011-11-07 06:44:47 +00:00
jhb
4270aed4c5 - Remove an unnecessary memory barrier from an atomic op.
- Use the per-softc mutex to protect the softc data in the callout routine
  rather than letting it run without any locks whatsoever.
2009-06-09 13:33:03 +00:00
ed
8d73adc757 Last minute TTY API change: remove mutex argument from tty_alloc().
I don't want people to override the mutex when allocating a TTY. It has
to be there, to keep drivers like syscons happy. So I'm creating a
tty_alloc_mutex() which can be used in those cases. tty_alloc_mutex()
should eventually be removed.

The advantage of this approach, is that we can just remove a function,
without breaking the regular API in the future.
2009-05-29 06:41:23 +00:00
ed
2e069b1e20 Make nmdm(4) use MPSAFE callouts.
For some reason the nmdm(4) driver doesn't use CALLOUT_MPSAFE, even
though we live in the MPSAFE TTY era. Add the CALLOUT_MPSAFE flags.
System survives.
2008-11-19 21:07:33 +00:00
ed
cc3116a938 Integrate the new MPSAFE TTY layer to the FreeBSD operating system.
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
2008-08-20 08:31:58 +00:00
ed
1bfc292986 Don't enforce unique device minor number policy anymore.
Except for the case where we use the cloner library (clone_create() and
friends), there is no reason to enforce a unique device minor number
policy. There are various drivers in the source tree that allocate unr
pools and such to provide minor numbers, without using them themselves.

Because we still need to support unique device minor numbers for the
cloner library, introduce a new flag called D_NEEDMINOR. All cdevsw's
that are used in combination with the cloner library should be marked
with this flag to make the cloning work.

This means drivers can now freely use si_drv0 to store their own flags
and state, making it effectively the same as si_drv1 and si_drv2. We
still keep the minor() and dev2unit() routines around to make drivers
happy.

The NTFS code also used the minor number in its hash table. We should
not do this anymore. If the si_drv0 field would be changed, it would no
longer end up in the same list.

Approved by:	philip (mentor)
2008-06-11 18:55:19 +00:00
emax
36a98790f4 Call ttyld_close() in nmdmclose() to ensure that nmdm(4)
closes line discipline installed onto /dev/nmdmX device.

Reviewed by:	julian
Approved by:	re (hrs)
MFC after:	3 days
2007-08-01 21:38:11 +00:00
rwatson
10d0d9cf47 Sweep kernel replacing suser(9) calls with priv(9) calls, assigning
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>
2006-11-06 13:42:10 +00:00
phk
527a24856d Use ttyalloc() instead of ttymalloc() 2006-01-04 08:34:23 +00:00
rwatson
daa1c89f45 Merge the dev_clone and dev_clone_cred event handlers into a single
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
2005-08-08 19:55:32 +00:00
phk
7af1e31761 Explicitly hold a reference to the cdev we have just cloned. This
closes the race where the cdev was reclaimed before it ever made it
back to devfs lookup.
2005-03-31 12:19:44 +00:00
phk
a6bb0e767e If CDSR_OFLOW (stty dsrflow) is enabled on one or both sides of a
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
2005-01-26 23:42:18 +00:00
imp
4b319958e7 Start each of the license/copyright comments with /*-, minor shuffle of lines 2005-01-06 01:43:34 +00:00
phk
8e1e714930 #include of <sys/vnode.h> not necesary. 2004-12-22 17:28:34 +00:00
phk
dafa1caf81 Add new function ttyinitmode() which sets our systemwide default
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.
2004-10-18 21:51:27 +00:00
phk
f00200d8a4 Preparation commit for the tty cleanups that will follow in the near
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.
2004-07-15 20:47:41 +00:00
phk
e58c00e142 Add modemcontrol support for DTR and DCD.
Tested by:	ambrisko
2004-07-04 16:27:58 +00:00
phk
40dd98a3bd Second half of the dev_t cleanup.
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.
2004-06-17 17:16:53 +00:00
phk
dfd1f7fd50 Do the dreaded s/dev_t/struct cdev */
Bump __FreeBSD_version accordingly.
2004-06-16 09:47:26 +00:00
phk
ba3920e2a2 Machine generated patch which changes linedisc calls from accessing
linesw[] directly to using the ttyld...() functions

The ttyld...() functions ar inline so there is no performance hit.
2004-06-04 16:02:56 +00:00
phk
1a00e2ae6b A major overhaul of the nmdm(4) driver:
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.
2004-06-01 22:53:00 +00:00
phk
e0c89dae13 There is no need to explicitly call the stop function. In all likelyhood
->l_close() did it and ttyclose certainly will.
2004-06-01 11:57:15 +00:00
phk
9d102d7d5a Add missing <sys/module.h> includes 2004-05-30 20:08:47 +00:00
imp
b49b7fe799 Remove advertising clause from University of California Regent's
license, per letter dated July 22, 1999 and email from Peter Wemm,
Alan Cox and Robert Watson.

Approved by: core, peter, alc, rwatson
2004-04-07 20:46:16 +00:00
phk
fdd216910f Add clone_setup() function rather than rely on lazy initialization.
Requested by:	rwatson
2004-03-11 12:58:55 +00:00
phk
ad925439e0 Device megapatch 4/6:
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.
2004-02-21 21:10:55 +00:00
phk
fcf7e634fb Device megapatch 3/6:
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.
2004-02-21 20:41:11 +00:00
phk
32b7c9a433 Device megapatch 2/6:
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.
2004-02-21 20:29:52 +00:00
tanimura
7eade05dfa - Implement selwakeuppri() which allows raising the priority of a
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
2003-11-09 09:17:26 +00:00
phk
050117a327 I don't know from where the notion that device driver should or
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.
2003-09-28 20:48:13 +00:00
obrien
c63dab466c Use __FBSDID().
Also some minor style cleanups.
2003-08-24 17:55:58 +00:00
das
5ba556c626 Make TTYHOG tunable.
Reviewed by:	mike (mentor)
2003-03-05 08:16:29 +00:00
phk
0ae911eb0e Gigacommit to improve device-driver source compatibility between
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)
2003-03-03 12:15:54 +00:00
imp
cf874b345d Back out M_* changes, per decision of the TRB.
Approved by: trb
2003-02-19 05:47:46 +00:00
alfred
bf8e8a6e8f Remove M_TRYWAIT/M_WAITOK/M_WAIT. Callers should use 0.
Merge M_NOWAIT/M_DONTWAIT into a single flag M_NOWAIT.
2003-01-21 08:56:16 +00:00
jhb
dc2e474f79 Change the suser() API to take advantage of td_ucred as well as do a
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@
2002-04-01 21:31:13 +00:00
jhb
3706cd3509 Simple p_ucred -> td_ucred changes to start using the per-thread ucred
reference.
2002-02-27 18:32:23 +00:00
julian
48024c8054 Cleanup of nmdm device 2002-02-20 20:13:13 +00:00
phk
cd01819509 Don't call cdevsw_add().
XXX: this driver lacks a proper _clone method.
2001-11-04 15:55:17 +00:00
julian
5596676e6c KSE Milestone 2
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
2001-09-12 08:38:13 +00:00
mp
f1340e224f Remove unused nmdmpoll function.
Approved by:	julian
2001-08-11 00:18:15 +00:00
phk
c47745e977 Send the remains (such as I have located) of "block major numbers" to
the bit-bucket.
2001-03-26 12:41:29 +00:00
julian
00392505c3 Remove warnings.. seems to compile as a module now too. 2001-02-27 17:52:49 +00:00
julian
7132567ff2 Catch up with rwatsons ucred changes. 2001-02-27 17:43:53 +00:00
julian
9bfaef2609 Do it right this time. Give it a better name and place
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 :-)
2001-02-27 16:39:54 +00:00