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
ALT_BREAK_TO_DEBUGGER. In addition to "Enter ~ ctrl-B" (to enter the
debugger), there is now "Enter ~ ctrl-P" (force panic) and
"Enter ~ ctrl-R" (request clean reboot, ala ctrl-alt-del on syscons).
We've used variations of this at work. The force panic sequence is
best used with KDB_UNATTENDED for when you just want it to dump and
get on with it.
The reboot request is a safer way of getting into single user than
a power cycle. eg: you've hosed the ability to log in (pam, rtld, etc).
It gives init the reboot signal, which causes an orderly reboot.
I've taken my best guess at what the !x86 and non-sio code changes
should be.
This also makes sio release its spinlock before calling KDB/DDB.
after each SYSINIT() macro invocation. This makes a number of
lightweight C parsers much happier with the FreeBSD kernel
source, including cflow's prcc and lxr.
MFC after: 1 month
Discussed with: imp, rink
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.
NULL and doesn't point to a NULL pointer before dereferencing it. This
fixes a panic triggered by Xorg 7.3.
Reported and tested by: Bill Green
MFC after: 3 days
to kproc_xxx as they actually make whole processes.
Thos makes way for us to add REAL kthread_create() and friends
that actually make theads. it turns out that most of these
calls actually end up being moved back to the thread version
when it's added. but we need to make this cosmetic change first.
I'd LOVE to do this rename in 7.0 so that we can eventually MFC the
new kthread_xxx() calls.
nxge: cast page size fragments down to (int). If the vm's demand paging
PAGE_SIZE is ever too big for that, we've got far bigger problems.
ofw: move va_start() a little earlier. gcc-4.2 doesn't like us modifying
the last arg before the va_start().
Approved by: re (rwatson)
moving OF_set_mmfsa_traptable() (SUNW,set-trap-table with the two
arguments used here is specific to sun4v) to MD code.
- In sys/dev/ofw/openfirm.h remove prototypes for unimplemented
functions and unused Solaris compatibility macros.
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>
a newly introduced struct ofw_bus_devinfo which can hold the OFW info
of a device recallable via the ofw_bus KOBJ interface. Introduce a set
of functions ofw_bus_gen_get_*() which use ofw_bus_default_get_devinfo()
to provide generic subroutines for implementing the rest of the ofw_bus
KOBJ interface in a bus driver.
This is inspired by bus_get_resource_list() and bus_generic_rl_*_resource()
and allows to reduce code duplication in bus drivers as they only have
to provide an ofw_bus_default_get_devinfo() implementation in order to
provide the ofw_bus KOBJ interface via ofw_bus_gen_get_*().
- While here add a comment to ofw_bus_if.m describing the intention of
the ofw_bus KOBJ interface.
Reviewed by: marcel
in bytes to start off with. This caused the GPT geom sniffer to attempt
a seek just back from the end of the 'disk', which resulted in a > 4G
seek, causing gdb psim to exit since it only supports 32-bit seeks.
The size of the disk should really be specified in the psim device tree,
but for now do the minimal amount of work to get psim to run again.
This allows boot to proceed on a real system until the issue
of calling back into certain OpenFirmware calls (e.g. finddevice)
in thread context is understood.
(this commit only affects psim users, of which I think I am the
only one...)
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.
subset ("compatible", "device_type", "model" and "name") of the standard
properties in drivers for devices on Open Firmware supported busses. The
standard properties "reg", "interrupts" und "address" are not covered by
this interface because they are only of interest in the respective bridge
code. There's a remaining standard property "status" which is unclear how
to support properly but which also isn't used in FreeBSD at present.
This ofw_bus kobj-interface allows to replace the various (ebus_get_node(),
ofw_pci_get_node(), etc.) and partially inconsistent (central_get_type()
vs. sbus_get_device_type(), etc.) existing IVAR ones with a common one.
This in turn allows to simplify and remove code-duplication in drivers for
devices that can hang off of more than one OFW supported bus.
- Convert the sparc64 Central, EBus, FHC, PCI and SBus bus drivers and the
drivers for their children to use the ofw_bus kobj-interface. The IVAR-
interfaces of the Central, EBus and FHC are entirely replaced by this. The
PCI bus driver used its own kobj-interface and now also uses the ofw_bus
one. The IVARs special to the SBus, e.g. for retrieving the burst size,
remain.
Beware: this causes an ABI-breakage for modules of drivers which used the
IVAR-interfaces, i.e. esp(4), hme(4), isp(4) and uart(4), which need to be
recompiled.
The style-inconsistencies introduced in some of the bus drivers will be
fixed by tmm@ in a generic clean-up of the respective drivers later (he
requested to add the changes in the "new" style).
- Convert the powerpc MacIO bus driver and the drivers for its children to
use the ofw_bus kobj-interface. This invloves removing the IVARs related
to the "reg" property which were unused and a leftover from the NetBSD
origini of the code. There's no ABI-breakage caused by this because none
of these driver are currently built as modules.
There are other powerpc bus drivers which can be converted to the ofw_bus
kobj-interface, e.g. the PCI bus driver, which should be done together
with converting powerpc to use the OFW PCI code from sparc64.
- Make the SBus and FHC front-end of zs(4) and the sparc64 eeprom(4) take
advantage of the ofw_bus kobj-interface and simplify them a bit.
Reviewed by: grehan, tmm
Approved by: re (scottl)
Discussed with: tmm
Tested with: Sun AX1105, AXe, Ultra 2, Ultra 60; PPC cross-build on i386
into single-user mode (as seen on sparc64 and PPC). Problems were due
to a minor oversight in the changes committed in revision 1.25.
Submitted by: grehan
Tested by: gad & yongari
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.
for unknown events.
A number of modules return EINVAL in this instance, and I have left
those alone for now and instead taught MOD_QUIESCE to accept this
as "didn't do anything".
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().
Ultra2 users may want to set OFWCONS_POLL_HZ to a value of '20'.
I have left default value at '4' as higher values can consume a more
than is acceptable amount of CPU, and we don't have a consensus yet
what is an optimal value.
Submitted by: Pyun YongHyeon <yongari@kt-is.co.kr>
identifiers, to openfirmio.h as OFIOCMAXNAME, so programs can use it
for buffer sizes etc.
Note: Although this is only a rough upper limit to make the code more
robust and to prevent the allocation of ridiculous amounts of memory,
the current limit of one page (8191 + '\0' in openfirm_getstr()) still
appears a bit high. The maximum length of OFW property names is 31.
I didn't find a maximum length for the device identifiers in the OFW
documentation but it certainly is much smaller than 8191, too.
- Enable the OFIOCSET ioctl, i.e. move it out from under #if 0.
- Don't use openfirm_getstr() for the property value in OFIOCSET, there
are also properties whose values aren't strings and it makes sense to
use a different maximum length for property values than OFW_NAME_MAX/
OFIOCMAXNAME. The maximum accepted property value is defined in
openfirmio.h as OFIOCMAXVALUE (currently the maximum size of the value
of the nvramrc property).
- Make OFIOCSET not return EINVAL when OF_setprop() returns a different
length for the written value than it was told to write, this is normal
for the text string values of the properties in the OFW /options node.
Instead, only return EINVAL if OF_setprop() returned -1 (value could
not be written or property could not be created). Add a comment about
the specialty of the OFW /options node.
- Make OFIOCSET return the length of the written value returned by
OF_setprop(), just like OF_getprop() does. Quite useful, at least for
debugging.
Reviewed by: tmm
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.
Free approx 86 major numbers with a mostly automatically generated patch.
A number of strategic drivers have been left behind by caution, and a few
because they still (ab)use their major number.
Previously the "struct disk" were owned by the device driver and this
gave us problems when the device disappared and the users of that device
were not immediately disappearing.
Now the struct disk is allocate with a new call, disk_alloc() and owned
by geom_disk and just abandonned by the device driver when disk_create()
is called.
Unfortunately, this results in a ton of "s/\./->/" changes to device
drivers.
Since I'm doing the sweep anyway, a couple of other API improvements
have been carried out at the same time:
The Giant awareness flag has been flipped from DISKFLAG_NOGIANT to
DISKFLAG_NEEDSGIANT
A version number have been added to disk_create() so that we can detect,
report and ignore binary drivers with old ABI in the future.
Manual page update to follow shortly.
the psim simulator. Look for the "file" property which only exists
on psim disks, and as a bonus, print the contents of this at boot-time,
which is the host file being used for the disk image.
- remove remaining warnings.
