IP6_EXTHDR_GET -> M_REGION_GET, no functional change.

Remove now unused tcpip.h includes. Some were already unused before.

Remove #ifdef INET. Same as tcp_input.c. Makes the code easier to
understand.

Also make tcp6_mtudisc() static in tcp_subr.c.

branches: 1.33.14;
Remove unnecessary inclusions of nd6.h

branches: 1.32.2;
sprinkle _KERNEL_OPT

Remove unnecessary opt_ipsec.h inclusions

branches: 1.30.2;
Do not uselessly include <sys/malloc.h>.

branches: 1.29.4;
* implement TCP CUBIC congestion control algorithm
* move tcp_sack_newack bits inside reno and newreno_fast_retransmit_newack
* notify ECN peer about cwnd shrink in [new]reno_slow_retransmit

Based on the patch proposed on tech-net@ on Nov 7 with minor improvments:
* adapt wmax for no-fast convergence case
* correct cbrt calculation for big window sizes (>750KB)

branches: 1.28.6; 1.28.10;
Use proper ANSI prototypes for foo() -> foo(void)
Caught when compiling with -Wold-style-definition

branches: 1.27.2; 1.27.6;
Retire varargs.h support. Move machine/stdarg.h logic into MI
sys/stdarg.h and expect compiler to provide proper builtins, defaulting
to the GCC interface. lint still has a special fallback.
Reduce abuse of _BSD_VA_LIST_ by defining __va_list by default and
derive va_list as required by standards.

- comments
- whitespace

branches: 1.25.4; 1.25.6;
POOL_INIT -> pool_init

branches: 1.24.14;
Remove clause 3 and 4 from TNF licenses

branches: 1.23.34; 1.23.36; 1.23.38;
Pass an ipl argument to pool_init/POOL_INIT to be used when initializing
the pool's lock.

branches: 1.22.4; 1.22.8;
add sack_dump(), a function to dump sack holes, if defined(DDB).

- constify.
- make tcp_dooptions and tcpipqent_pool static.

Fix alignment problems causing regular panics in tpc_sack_option on
NetBSD/alpha and NetBSD/sparc. This fixes PR#34751.

The problem most likely started to show in gcc4 and is caused by the use of
a casting to an uint32_t pointer that is later copied from using memcpy.
Gcc detects the copying of 4 bytes from an uint32_t pointer and decides to
just replace it with an aligned copy causing the trap.

Fix provided by Izumi Tsutsui and ok'd by Martin.

- make sackhole_pool static.
- unify duplicated hole allocation and accounting code.
(no functional changes.)

revert tcp_sack.c rev.1.15 because it's unnecessary.
all callers of these functions are at splsoftnet already:
tcp_sack_option
tcp_input ok

tcp_del_sackholes
tcp_input ok

tcp_free_sackholes
tcp_close ok
tcp_timer_rexmt ok
tcp_timer_2msl ok

tcp_sack_output: whitespace.

tcp_del_sackholes: whitespace.

Protect calls to pool_put/pool_get that may occur in interrupt context
with spl used to protect other allocations and frees, or datastructure
element insertion and removal, in adjacent code.

It is almost unquestionably the case that some of the spl()/splx() calls
added here are superfluous, but it really seems wrong to see:

s=splfoo();
/* frob data structure */
splx(s);
pool_put(x);

and if we think we need to protect the first operation, then it is hard
to see why we should not think we need to protect the next. "Better
safe than sorry".

It is also almost unquestionably the case that I missed some pool
gets/puts from interrupt context with my strategy for finding these
calls; use of PR_NOWAIT is a strong hint that a pool may be used from
interrupt context but many callers in the kernel pass a "can wait/can't
wait" flag down such that my searches might not have found them. One
notable area that needs to be looked at is pf.

See also:

http://mail-index.netbsd.org/tech-kern/2006/07/19/0003.html
http://mail-index.netbsd.org/tech-kern/2006/07/19/0009.html

branches: 1.14.4; 1.14.20; 1.14.22;
merge ktrace-lwp.

branches: 1.13.2;
tcp_sack_option: ignore sack beyond snd_max.

branches: 1.12.2;
Added sysctl tunable limits for the number of maximum SACK holes
per connection and per system.

Idea taken from FreeBSD.

branches: 1.11.2;
TCP/SACK changes from FreeBSD.

Ignore the SACK option if
* The packet is not an ACK.
* The ACK is outside of snd_una -> snd_max

branches: 1.10.2;
simplify data receiver side sack processing.
- introduce t_segqlen, the number of segments in segq/timeq.
the name is from freebsd.
- rather than maintaining a copy of sack blocks (rcv_sack_block[]),
build it directly from the segment list when needed.

- use full sized segments unless we actually have SACKs to send.
- avoid TSO duplicate D-SACK.
- send SACKs regardless of TF_ACKNOW.
- don't clear rcv_sack_num when transmitting.

discussed on tech-net@.

tcp_sack_option: handle the case that the right-most sack'ed block is expanded.
a fix from Noritoshi Demizu (FreeBSD PR/78226) via Kentaro A. Kurahone.

tcp_sack_option: fix the cases that some sack blocks go into a hole.

tcp_sack_option: fix a typo(?), which can cause to ignore valid blocks.

tcp_sack_option: the max number of sack blocks in a packet is 4, not 3.

- unwrap short lines.
- remove unneeded parenthesis.
- whitespace.

don't assume alignment of sack options.

wrap long lines.

branches: 1.1.2;
Commit TCP SACK patches from Kentaro A. Karahone's patch at:
http://www.sigusr1.org/~kurahone/tcp-sack-netbsd-02152005.diff.gz

Fixes in that patch for pre-existing TCP pcb initializations were already
committed to NetBSD-current, so are not included in this commit.

The SACK patch has been observed to correctly negotiate and respond,
to SACKs in wide-area traffic.

There are two indepenently-observed, as-yet-unresolved anomalies:
First, seeing unexplained delays between in fast retransmission
(potentially explainable by an 0.2sec RTT between adjacent
ethernet/wifi NICs); and second, peculiar and unepxlained TCP
retransmits observed over an ath0 card.

After discussion with several interested developers, I'm committing
this now, as-is, for more eyes to use and look over. Current hypothesis
is that the anomalies above may in fact be due to link/level (hardware,
driver, HAL, firmware) abberations in the test setup, affecting both
Kentaro's wired-Ethernet NIC and in my two (different) WiFi NICs.

Remove unnecessary inclusions of nd6.h

sprinkle _KERNEL_OPT

Remove unnecessary opt_ipsec.h inclusions

branches: 1.30.2;
Do not uselessly include <sys/malloc.h>.

branches: 1.29.4;
* implement TCP CUBIC congestion control algorithm
* move tcp_sack_newack bits inside reno and newreno_fast_retransmit_newack
* notify ECN peer about cwnd shrink in [new]reno_slow_retransmit

Based on the patch proposed on tech-net@ on Nov 7 with minor improvments:
* adapt wmax for no-fast convergence case
* correct cbrt calculation for big window sizes (>750KB)

branches: 1.28.6; 1.28.10;
Use proper ANSI prototypes for foo() -> foo(void)
Caught when compiling with -Wold-style-definition

branches: 1.27.2; 1.27.6;
Retire varargs.h support. Move machine/stdarg.h logic into MI
sys/stdarg.h and expect compiler to provide proper builtins, defaulting
to the GCC interface. lint still has a special fallback.
Reduce abuse of _BSD_VA_LIST_ by defining __va_list by default and
derive va_list as required by standards.

- comments
- whitespace

branches: 1.25.4; 1.25.6;
POOL_INIT -> pool_init

branches: 1.24.14;
Remove clause 3 and 4 from TNF licenses

branches: 1.23.34; 1.23.36; 1.23.38;
Pass an ipl argument to pool_init/POOL_INIT to be used when initializing
the pool's lock.

branches: 1.22.4; 1.22.8;
add sack_dump(), a function to dump sack holes, if defined(DDB).

- constify.
- make tcp_dooptions and tcpipqent_pool static.

Fix alignment problems causing regular panics in tpc_sack_option on
NetBSD/alpha and NetBSD/sparc. This fixes PR#34751.

The problem most likely started to show in gcc4 and is caused by the use of
a casting to an uint32_t pointer that is later copied from using memcpy.
Gcc detects the copying of 4 bytes from an uint32_t pointer and decides to
just replace it with an aligned copy causing the trap.

Fix provided by Izumi Tsutsui and ok'd by Martin.

- make sackhole_pool static.
- unify duplicated hole allocation and accounting code.
(no functional changes.)

revert tcp_sack.c rev.1.15 because it's unnecessary.
all callers of these functions are at splsoftnet already:
tcp_sack_option
tcp_input ok

tcp_del_sackholes
tcp_input ok

tcp_free_sackholes
tcp_close ok
tcp_timer_rexmt ok
tcp_timer_2msl ok

tcp_sack_output: whitespace.

tcp_del_sackholes: whitespace.

Protect calls to pool_put/pool_get that may occur in interrupt context
with spl used to protect other allocations and frees, or datastructure
element insertion and removal, in adjacent code.

It is almost unquestionably the case that some of the spl()/splx() calls
added here are superfluous, but it really seems wrong to see:

s=splfoo();
/* frob data structure */
splx(s);
pool_put(x);

and if we think we need to protect the first operation, then it is hard
to see why we should not think we need to protect the next. "Better
safe than sorry".

It is also almost unquestionably the case that I missed some pool
gets/puts from interrupt context with my strategy for finding these
calls; use of PR_NOWAIT is a strong hint that a pool may be used from
interrupt context but many callers in the kernel pass a "can wait/can't
wait" flag down such that my searches might not have found them. One
notable area that needs to be looked at is pf.

See also:

http://mail-index.netbsd.org/tech-kern/2006/07/19/0003.html
http://mail-index.netbsd.org/tech-kern/2006/07/19/0009.html

branches: 1.14.4; 1.14.20; 1.14.22;
merge ktrace-lwp.

branches: 1.13.2;
tcp_sack_option: ignore sack beyond snd_max.

branches: 1.12.2;
Added sysctl tunable limits for the number of maximum SACK holes
per connection and per system.

Idea taken from FreeBSD.

branches: 1.11.2;
TCP/SACK changes from FreeBSD.

Ignore the SACK option if
* The packet is not an ACK.
* The ACK is outside of snd_una -> snd_max

branches: 1.10.2;
simplify data receiver side sack processing.
- introduce t_segqlen, the number of segments in segq/timeq.
the name is from freebsd.
- rather than maintaining a copy of sack blocks (rcv_sack_block[]),
build it directly from the segment list when needed.

- use full sized segments unless we actually have SACKs to send.
- avoid TSO duplicate D-SACK.
- send SACKs regardless of TF_ACKNOW.
- don't clear rcv_sack_num when transmitting.

discussed on tech-net@.

tcp_sack_option: handle the case that the right-most sack'ed block is expanded.
a fix from Noritoshi Demizu (FreeBSD PR/78226) via Kentaro A. Kurahone.

tcp_sack_option: fix the cases that some sack blocks go into a hole.

tcp_sack_option: fix a typo(?), which can cause to ignore valid blocks.

tcp_sack_option: the max number of sack blocks in a packet is 4, not 3.

- unwrap short lines.
- remove unneeded parenthesis.
- whitespace.

don't assume alignment of sack options.

wrap long lines.

branches: 1.1.2;
Commit TCP SACK patches from Kentaro A. Karahone's patch at:
http://www.sigusr1.org/~kurahone/tcp-sack-netbsd-02152005.diff.gz

Fixes in that patch for pre-existing TCP pcb initializations were already
committed to NetBSD-current, so are not included in this commit.

The SACK patch has been observed to correctly negotiate and respond,
to SACKs in wide-area traffic.

There are two indepenently-observed, as-yet-unresolved anomalies:
First, seeing unexplained delays between in fast retransmission
(potentially explainable by an 0.2sec RTT between adjacent
ethernet/wifi NICs); and second, peculiar and unepxlained TCP
retransmits observed over an ath0 card.

After discussion with several interested developers, I'm committing
this now, as-is, for more eyes to use and look over. Current hypothesis
is that the anomalies above may in fact be due to link/level (hardware,
driver, HAL, firmware) abberations in the test setup, affecting both
Kentaro's wired-Ethernet NIC and in my two (different) WiFi NICs.