Add a COMMENT describing what each component roughly does.

"make describe" prints the comment.

Requested/inspired by Vincent Schwarzer on rumpkernel-users

branches: 1.5.6;
rename component.c -> netinet_component.c

branches: 1.4.12; 1.4.22; 1.4.26;
Include component.c instead of dummy.c so that domain constructors
get properly called.

branches: 1.3.2; 1.3.10; 1.3.16;
Deal with the ld.so/linkset brokenness and compile all of libnet
and libnetinet into a big bunch for now. If they were separate
libraries, the DOMAIN_DEFINE() in the latter on the linkline would
not get noticed at "boot" time because of the abovementioned
brokenness. One of these days I'll add code to dlopen() the
libraries and resplit them, but this will allow things to work
until then.

Add tcp debugging as a build option.

branches: 1.1.2;
Provide the TCP/IP as a rump library.

tcp: separate syn cache stuffs into tcp_syncache.[ch] files

No functional change.

remove ip{,6}_id.c

branches: 1.14.24;
Rumpify netipsec

Note that we should modularize netipsec and reduce reverse symbol references
(referencing symbols of netipsec from net, netinet and netinet6) though,
the task needs lots of code changes. Prior to doing so, rumpifying it and
having ATF tests should be useful.

branches: 1.13.2; 1.13.4;
purge rump/net of component-specific opt directories

Move defines of INET and INET6 from opt_inet.h to Makefile.inc

As discussed with pooka@
fixes current issues with ipv6 on rump being broken

branches: 1.11.6;
Separate inet and inet6, allows inet6-only rump kernels.

branches: 1.10.2;
default portalgo to random_start, for less connections from port 65535

cosmetic: put portalgo.c in the conceptually right place

branches: 1.8.4; 1.8.14;
Reduces the resources demanded by TCP sessions in TIME_WAIT-state using
methods called Vestigial Time-Wait (VTW) and Maximum Segment Lifetime
Truncation (MSLT).

MSLT and VTW were contributed by Coyote Point Systems, Inc.

Even after a TCP session enters the TIME_WAIT state, its corresponding
socket and protocol control blocks (PCBs) stick around until the TCP
Maximum Segment Lifetime (MSL) expires. On a host whose workload
necessarily creates and closes down many TCP sockets, the sockets & PCBs
for TCP sessions in TIME_WAIT state amount to many megabytes of dead
weight in RAM.

Maximum Segment Lifetimes Truncation (MSLT) assigns each TCP session to
a class based on the nearness of the peer. Corresponding to each class
is an MSL, and a session uses the MSL of its class. The classes are
loopback (local host equals remote host), local (local host and remote
host are on the same link/subnet), and remote (local host and remote
host communicate via one or more gateways). Classes corresponding to
nearer peers have lower MSLs by default: 2 seconds for loopback, 10
seconds for local, 60 seconds for remote. Loopback and local sessions
expire more quickly when MSLT is used.

Vestigial Time-Wait (VTW) replaces a TIME_WAIT session's PCB/socket
dead weight with a compact representation of the session, called a
"vestigial PCB". VTW data structures are designed to be very fast and
memory-efficient: for fast insertion and lookup of vestigial PCBs,
the PCBs are stored in a hash table that is designed to minimize the
number of cacheline visits per lookup/insertion. The memory both
for vestigial PCBs and for elements of the PCB hashtable come from
fixed-size pools, and linked data structures exploit this to conserve
memory by representing references with a narrow index/offset from the
start of a pool instead of a pointer. When space for new vestigial PCBs
runs out, VTW makes room by discarding old vestigial PCBs, oldest first.
VTW cooperates with MSLT.

It may help to think of VTW as a "FIN cache" by analogy to the SYN
cache.

A 2.8-GHz Pentium 4 running a test workload that creates TIME_WAIT
sessions as fast as it can is approximately 17% idle when VTW is active
versus 0% idle when VTW is inactive. It has 103 megabytes more free RAM
when VTW is active (approximately 64k vestigial PCBs are created) than
when it is inactive.

branches: 1.7.2;
Support carp. It would be nice to support this as its own component,
but there's about 1000 lines of #ifdef which disagree with my wish.

Split-off IPv4 re-assembly mechanism into a separate module. Abstract
into ip_reass_init(), ip_reass_lookup(), etc (note: abstraction is not
yet complete). No functional changes to the actual mechanism.

OK matt@

branches: 1.5.2;
Globally define -Wno-pointer-sign, as it has become a pointless
exercise of "add it to every Makefile individually".

XXX: should autosynchronize with the rest of the kernel buildflags
in sys/conf/Makefile.kern.inc.

branches: 1.4.2;
Support IPv6 in rump. I'd have liked to introduce a netinet6
component, but due to ifdef happiness permeating the sources, it's
a compile decision for now, so netinet pulls in both inet and inet6.

One issue, one single issue: the loopback interface still needs to
be created for IPv6 to work. I have patches to take care of it
automatically if the appropriate component (net) is present, but
they require a bit more testing before commit.

branches: 1.3.2; 1.3.4;
Better define GATEWAY in opt_gateway.h instead of the Makefile so
UPDATE builds don't go all coocoo.

enable GATEWAY

branches: 1.1.2; 1.1.4; 1.1.10;
Deal with the ld.so/linkset brokenness and compile all of libnet
and libnetinet into a big bunch for now. If they were separate
libraries, the DOMAIN_DEFINE() in the latter on the linkline would
not get noticed at "boot" time because of the abovementioned
brokenness. One of these days I'll add code to dlopen() the
libraries and resplit them, but this will allow things to work
until then.

rename component.c -> netinet_component.c

Register netisr's from component constructors instead of via a hardcoded
global list.

Allow kernels compiled with INET+INET6 to be booted as IPv4-only or IPv6-only.

Partially revert previous, there are still a few gotchas in
running ipv4/ipv6-only (too many dependencies on ifdefs).

Separate inet and inet6, allows inet6-only rump kernels.

Raise lo0 so that ipv6 config gets done for it.

Requested and tested by Justin Cormack.

branches: 1.5.8; 1.5.18; 1.5.22;
Ensure that a) loopback attaches after all the domains have attached
b) loopback is configured only after it has attached.

makes tests/net/if_loop work again

Autoconfigure 127.0.0.1 for lo0.
(testing bind/connect/etc. is now possible on a virgin rump kernel
without the need to ifconfig anything)

Support carp. It would be nice to support this as its own component,
but there's about 1000 lines of #ifdef which disagree with my wish.

branches: 1.2.2;
Introduce RUMP_COMPONENT. It behaves mostly like a simplified
module which is linked into the kernel and cannot be unloaded.
The main purpose is to get the proper constructors run and create
any /dev nodes necessary for said component. Once more of the
kernel (e.g. networking stack and device drivers) are converted to
MODULE and devfs pops up from somewhere, rump components can be
retired.

branches: 1.1.2; 1.1.4;
Use a bunch of weak symbols to determine which network components
are present. This works in userspace as opposed relying in link
sets, which fail miserably. Later, when the networking stack
becomes modularized, we can move to a dynamic scheme like with file
systems.

Also, this change allows us to do proper autoconfig, namely attach
the loopback interface iff it is present.

Include component.c instead of dummy.c so that domain constructors
get properly called.

branches: 1.1.2; 1.1.10; 1.1.16;
Deal with the ld.so/linkset brokenness and compile all of libnet
and libnetinet into a big bunch for now. If they were separate
libraries, the DOMAIN_DEFINE() in the latter on the linkline would
not get noticed at "boot" time because of the abovementioned
brokenness. One of these days I'll add code to dlopen() the
libraries and resplit them, but this will allow things to work
until then.

Garbage-collect the remaining vestiges of netisr.

Convert ARP from a legacy netisr to pktqueue.

Avoid a deadlock between softnet_lock and IFNET_LOCK

A deadlock occurs because there is a violation of the rule of lock ordering;
softnet_lock is held with hodling IFNET_LOCK, which violates the rule.
To avoid the deadlock, replace softnet_lock in in_control and in6_control
with KERNEL_LOCK.

We also need to add some KERNEL_LOCKs to protect the network stack surely.
This is required, for example, for PR kern/51356.

Fix PR kern/53043

Wrap if_ioctl_lock with IFNET_* macros (NFC)

Also if_ioctl_lock perhaps needs to be renamed to something because it's now
not just for ioctl...

Ensure to call if_addr_init with holding if_ioctl_lock

branches: 1.8.6;
Protect if_clone data with if_clone_mtx

To this end, carpattach needs to be delayed from RUMP_COMPONENT_NET to
RUMP_COMPONENT_NET_IF on rump_server. Otherwise mutex_enter via carpattach
for if_clone_mtx is called before mutex_init for it in ifinit1.

branches: 1.7.2;
Don't call loopinit() here. Instead panic if -lrumpnet_net has not been
called to initialize lo0ifp.

more loopinit();

branches: 1.5.2;
Put the kernelside rump kernel headers into <rump-sys> instead of
sprinkling them around the faction directories. Avoids having
to add a CPPFLAGS (or several) to pretty much every component
Makefile.

Leave compat headers around in the old locations.

The commit changes some autogenerated files, but I'll fix the
generators shortly and regen.

branches: 1.4.2;
Nuke the DOMAINADD() macro and just call domain_attach(), now that things
work correctly that way.

branches: 1.3.4;
fix parameter types in pr_ioctl, called xx_control() functions and remove
abuse of pointer to struct mbuf type.

param2 changed to u_long type and uses parameter name 'cmd' (ioctl command)
param3 changed to void * type and uses parameter name 'data'
param4 changed to struct ifnet * and uses parameter name 'ifp'
param5 has been removed (formerly struct lwp *) and uses of 'l' have been
replaced with curlwp from curproc(9).

callers have had (now unnecessary) casts to struct mbuf * removed, called
code has had (now unnecessary) casts to u_long, void * and struct ifnet *
respectively removed.

reviewed by rmind@

- Implement pktqueue interface for lockless IP input queue.
- Replace ipintrq and ip6intrq with the pktqueue mechanism.
- Eliminate kernel-lock from ipintr() and ip6intr().
- Some preparation work to push softnet_lock out of ipintr().

Discussed on tech-net.

branches: 1.1.2; 1.1.4; 1.1.6;
rename component.c -> netinet_component.c

Remove shlib_version files and just use Makefile SHLIB_MAJOR/MINOR,
with the default provided by Makefile.rump (they're all 0.0 anyway)

branches: 1.1.2; 1.1.4; 1.1.12; 1.1.18; 1.1.46; 1.1.66;
Provide the TCP/IP as a rump library.