before adding/removing packets from the queue. Also, the if_obytes and
if_omcasts fields should only be manipulated under protection of the mutex.
IF_ENQUEUE, IF_PREPEND, and IF_DEQUEUE perform all necessary locking on
the queue. An IF_LOCK macro is provided, as well as the old (mutex-less)
versions of the macros in the form _IF_ENQUEUE, _IF_QFULL, for code which
needs them, but their use is discouraged.
Two new macros are introduced: IF_DRAIN() to drain a queue, and IF_HANDOFF,
which takes care of locking/enqueue, and also statistics updating/start
if necessary.
usb_ethersubr.c. This module maintains two queues for packets which
are each protected with one mutex. These are all the changes I can
do for now. Removing the USBD_NO_TSLEEP flag doesn't work yet: when
I tried it, the system would usually freeze up after a NIC had been
operating for a while. The usb_ethersubr module itself ought to
go away; this is the next thing I need to test.
of the individual drivers and into the common routine ether_input().
Also, remove the (incomplete) hack for matching ethernet headers
in the ip_fw code.
The good news: net result of 1016 lines removed, and this should make
bridging now work with *all* Ethernet drivers.
The bad news: it's nearly impossible to test every driver, especially
for bridging, and I was unable to get much testing help on the mailing
lists.
Reviewed by: freebsd-net
Do not not not call m_freem() in the txeof routines. Let the netisr routine
do it. This also makes the tx netisr queuing much simpler (I can just use
another ifqueue instead of the mess I had before.)
Thanks to Bosko Milekic for making me actually think about what I was
doing for a minute.
- Add vendor/device ID for Corega USB-T ethernet adapter to necessary
places so that it will work with the kue driver.
- Add vendor/device ID for CATC Netmate devices for driver to be added
soon.
- Get really crazy about netisr stuff: avoid doing any mbuf allocations
or deallocations at splbio/splusb.
- Fix if_aue driver so that it works with LinkSys USB100TX: you need
to flip the GPIO bits just the right way to put the PHY in the right
mode.
drive the transmitter, we have to check the interface's send queue in the
TX end of frame handler (i.e. the usb bulk out callback) and push out new
transmissions if the queue has packets in it and the transmitter is
ready. But the txeof handler is also called from a USB callback running
at splusb() too.
Grrr.
Packets are received inside USB bulk transfer callbacks, which run at
splusb() (actually splbio()). The packet input queues are meant to be
manipulated at splimp(). However the locking apparently breaks down under
certain circumstances and the input queues can get trampled.
There's a similar problem with if_ppp, which is driven by hardware/tty
interrupts from the serial driver, but which must also manipulate the
packet input queues at splimp(). The fix there is to use a netisr, and
that's the fix I used here. (I can hear you groaning back there. Hush up.)
The usb_ethersubr module maintains a single queue of its own. When a
packet is received in the USB callback routine, it's placed on this
queue with usb_ether_input(). This routine also schedules a soft net
interrupt with schednetisr(). The ISR routine then runs later, at
splnet, outside of the USB callback/interrupt context, and passes the
packet to ether_input(), hopefully in a safe manner.
The reason this is implemented as a separate module is that there are
a limited number of NETISRs that we can use, and snarfing one up for
each driver that needs it is wasteful (there will be three once I get
the CATC driver done). It also reduces code duplication to a certain
small extent. Unfortunately, it also needs to be linked in with the
usb.ko module in order for the USB ethernet drivers to share it.
Also removed some uneeded includes from if_aue.c and if_kue.c
Fix suggested by: peter
Not rejected as a hairbrained idea by: n_hibma
