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
corresponding USAGE should be skipped as well.
For example, below is a report desc fragment of some mouse:
COLLECTION
...
USAGE TWHEEL
FEATURE ...
...
USAGE WHEEL
INPUT ...
...
END COLLECTION
"USAGE TWHEEL" should be consumed after the FEATURE item is skipped,
otherwise, the INPUT item will be assigned to "USAGE TWHEEL" later,
other than "USAGE WHEEL".
Tested by: Grzegorz Blach
PR: usb/125941
This driver supports GW3887 based chipsets and works on
x86/powerpc/sparc64. You need upgtfw kernel module before loading
upgt(4). Please see the manpage.
Obtained from: OpenBSD
The kbd, kbdmux, ugen and uhid drivers included <sys/tty.h>, because
they needed clists, which have been moved to <sys/clist.h> some time
ago. In the MPSAFE TTY branch, <sys/tty.h> does not include
<sys/clist.h>, which means we have to teach these drivers to include
this header file directly.
Approved by: philip (mentor, implicit)
dispatched without Giant, and add NETISR_FORCEQUEUE, which allows specific
netisr handlers to always be dispatched via a queue (deferred). Mark the
usb and if_ppp netisr handlers as NETISR_FORCEQUEUE, and explicitly
acquire Giant in those handlers.
Previously, any netisr handler not marked NETISR_MPSAFE would necessarily
run deferred and with Giant acquired. This change removes Giant
scaffolding from the netisr infrastructure, but NETISR_FORCEQUEUE allows
non-MPSAFE handlers to continue to force deferred dispatch so as to avoid
lock order reversals between their acqusition of Giant and any calling
context.
It is likely we will be able to remove NETISR_FORCEQUEUE once
IFF_NEEDSGIANT is removed, as non-MPSAFE usb and if_ppp drivers will no
longer be supported.
Reviewed by: bz
MFC after: 1 month
X-MFC note: We can't remove NETISR_MPSAFE from stable/7 for KPI reasons,
but the rest can go back.
Remove the code which disables port status change interrupts for 1s
when one occured -- this makes that events get lost or delayed until
the next change.
Obtained from: NetBSD
some longstanding issues:
o pass the vap since it's now the "coin of the realm" and required
to do things like set initial tx parameters in private node
state for use prior to association
o pass the mac address as cards that maintain outboard station
tables require this to create an entry (e.g. in ibss mode)
o remove the node table reference, we only have one node table
and it's unlikely this will change so this is not needed to
find the com structure
Add support for the Apple USB Ethernet adapter.
Work around the "latch in at the first working PHY address hack",
that fails for this adapter because it returns 0xffff when reading
from lower PHY addresses. Also add more debugging printfs
Obtained from: OpenBSD
MFC After: 3 days
o correct mapping of CCK rates to PLCP; was using nonstandard Ralink
values which just happened to also be used by Zydas (so went unnoticed)
o change ieee80211_plcp2rate api to take a phy type instead of a flag
that indicates ofdm/!ofdm
o update drivers to match (restore per-driver code to map rate->PLCP)
Reviewed by: sephe, weongyo, thompsa
o add IEEE80211_C_STA capability to indicate sta mode is supported
(was previously assumed) and mark drivers as capable
o add ieee80211_opcap array to map an opmode to the equivalent capability bit
o move IEEE80211_C_OPMODE definition to where capabilities are defined so it's
clear it should be kept in sync (on future additions)
o check device capabilities in clone create before trying to create a vap;
this makes driver checks unneeded
o make error codes return on failed clone request unique
o temporarily add console printfs on clone request failures to aid in
debugging; these will move under DIAGNOSTIC or similar before release
- Limit grabbing the lock to SIOCSIFFLAGS.
- Move ieee80211_start_all() to SIOCSIFFLAGS.
- Remove SIOCSIFMEDIA as it is not useful.
- Limit ether_ioctl to only SIOCGIFADDR. SIOCSIFADDR and SIOCSIFMTU have no
affect as there is no input/output path in the vap parent. The vap code
will handle the reinit of the mac address changes.
- Split off ndis_ioctl_80211 as it was getting too different to wired devices.
This fixes a copyout while locked and a lock recursion.
Reviewed by: sam
Note this includes changes to all drivers and moves some device firmware
loading to use firmware(9) and a separate module (e.g. ral). Also there
no longer are separate wlan_scan* modules; this functionality is now
bundled into the wlan module.
Supported by: Hobnob and Marvell
Reviewed by: many
Obtained from: Atheros (some bits)
I've taken a slightly different approach than is used with the ICH8 controllers
in that each controller is not identified individually (eg USB A, USB B, etc).
Instead I've given then same description to each one even though the device ID
differs. This can easily be changed if desired, or ICH8 (and any others using
that approach) can be made to work as this does.
