inbound data waiting on a filedescriptor, such as a pipe or a socket,
for instance by using select(2), poll(2), kqueue(2), ioctl(FIONREAD)
etc.
But we have no way of finding out if written data have yet to be
disposed of, for instance, transmitted (and ack'ed!) to some remote
host, or read by the applicantion at the far end of the pipe.
The closest we get, is calling shutdown(2) on a TCP socket in
non-blocking mode, but this has the undesirable sideeffect of
preventing future communication.
Add a complement to FIONREAD, called FIONWRITE, which returns the
number of bytes not yet properly disposed of. Implement it for
all sockets.
Background:
A HTTP server will want to time out connections, if no new request
arrives within a certain period after the last transmitted response
has actually been sent (and ack'ed).
For a busy HTTP server, this timeout can be subsecond duration.
In order to signal to a load-balancer that the connection is truly
dead, TCP_RST will be the preferred method, as this avoids the need
for a RTT delay for FIN handshaking, with a client which, surprisingly
often, no longer at the remote IP number.
If a slow, distant client is being served a response which is big
enough to fill the window, but small enough to fit in the socket
buffer, the write(2) call will return immediately.
If the session timeout is armed at that time, all bytes in the
response may not have been transmitted by the time it fires.
FIONWRITE allows the timeout to check that no data is outstanding
on the connection, before it TCP_RST's it.
Input & Idea from: rwatson
Approved by: re (kib)
o add HAL_CAP_BSSIDMATCH to identify parts that have the support for
disabling bssid match
o honor capability for set/get rx filter
o use HAL_CAP_BSSIDMATCH in driver to decide whether to use the bssid
match disable or fall back to promisc mode
Reviewed by: rpaulo
Approved by: re (rwatson)
o add 9280 attach that sets up ini, cal, etc.
o new rf backend for 9280 and later parts
o split ini setup and spur mitigation support out to methods
and provide 9280-specific support
o minor fixups to shared code to handle 9280-specific work
Obtained from: Atheros (ini values and some code)
o add ah_configPCIE and ah_disablePCIE for drivers to configure PCIE
power save operation (modeled after ath9k, may need changes)
o add private state flag to indicate if device is PCIE (replaces private
hack in 5212 code)
o add serdes programming ini bits for 5416 and later parts and setup
for each part (5416 and 9160 logic hand-crafted from existing routines);
5212 remains open-coded but is now hooked in via ah_configPCIE
o add PCIE workaround gunk
o add ar5416AttachPCIE for iodomatic code used by 5416 and later parts
o add output mux support
o gpio pin count is chip-dependent
o 9280 and 9285 do input handling different
o hookup gpio interrupts
o no need to save/restore soft led state around reset
o mark phy type to indicate 1/2 or 1/4-rate operation
o use phy type instead of channel attributes to identify 1/2 and 1/4-rate
operation
o general cleanup of code including move phy constants to ah_internal.h
Eventually this code should go away and we should use the net0211 equivalents.
guaranteed to initialize its two last arguments. Therefore, there is a
warning in the subsequent caller ar5416FillVpdTable(), which doesn't
initialize those arguments.
Change getLowerUpperIndex() to assign values to indexL and indexR even
in the case of assertion failure.
Submitted by: Pavel Roskin <proski@gnu.org>
