net: attach IPv4 and IPv6 stacks to an interface with EVENTHANDLER(9)

This change retires two historic relics: the if_afdata[] array and the
dom_ifattach/dom_ifdetach methods.

The if_afdata[] array

net: attach IPv4 and IPv6 stacks to an interface with EVENTHANDLER(9)

This change retires two historic relics: the if_afdata[] array and the
dom_ifattach/dom_ifdetach methods.

The if_afdata[] array is a relic of the era, when there was expectation
that many transport protocols will coexist with IP, e.g. IPX or NetAtalk.
The array hasn't had any members except AF_INET and AF_INET6 for over a
decade already. This change removes the array and just leaves two pointer
fields: if_inet and if_inet6.

The dom_ifattach/dom_ifdetach predates the EVENTHANDLER(9) framework and
was a good enough method to initialize protocol contexts back then. Today
there is no good reason to treat IPv4 and IPv6 stacks differently to other
protocols/features that attach and detach from an interface.

The locking of if_afdata[] is a relic of SMPng times, when the system
startup and the interface attach was even more convoluted than before this
change, and we also had unloadable protocols that used a field in
if_afdata[]. Note that IPv4 and IPv6 are not unloadable.

Note that this change removes NET_EPOCH_WAIT() from the interface detach
sequence. This may surface several new races associated with interface
removal. I failed to hit any with consecutive test suite runs, though.
The expected general race scenario is that while struct ifnet is freed
with proper epoch_call(9) itself, some structures hanging off ifnet are
freed with direct free(9). The proper fix is either make if_foo point at
some static "dead" structure providing SMP visibility of this store, or
free those structure with epoch_call(9). All of these cases are planned
to be found and resolved during 16.0-CURRENT lifetime.

Reviewed by: zlei, gallatin, melifaro
Differential Revision: https://reviews.freebsd.org/D54089

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sockets: remove dom_externalize

It was used only by unix(4) and now is completely isolated.

sockets: garbage collect SB_NOINTR

Not used. All socket buffer sleeps are interruptible.

sockets: garbage collect SS_ISCONFIRMING

Fixes: 8df32b19dee92b5eaa4b488ae78dca6accfcb38e

sockets: remove dom_dispose and PR_RIGHTS

Passing file descriptors (rights) via sockets is a feature specific to
PF_UNIX only, so fully isolate the logic into uipc_usrreq.c.

Reviewed by: tuexen
Di

sockets: remove dom_dispose and PR_RIGHTS

Passing file descriptors (rights) via sockets is a feature specific to
PF_UNIX only, so fully isolate the logic into uipc_usrreq.c.

Reviewed by: tuexen
Differential Revision: https://reviews.freebsd.org/D43414

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sys: Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

show more ...

domains: use queue(9) SLIST for linked list of domains

protosw: retire pr_drain and use EVENTHANDLER(9) directly

The method was called for two different conditions: 1) the VM layer is
low on pages or 2) one of UMA zones of mbuf allocator exhausted.
This

protosw: retire pr_drain and use EVENTHANDLER(9) directly

The method was called for two different conditions: 1) the VM layer is
low on pages or 2) one of UMA zones of mbuf allocator exhausted.
This change 2) into a new event handler, but all affected network
subsystems modified to subscribe to both, so this change shall not
bring functional changes under different low memory situations.

There were three subsystems still using pr_drain: TCP, SCTP and frag6.
The latter had its protosw entry for the only reason to register its
pr_drain method.

Reviewed by: tuexen, melifaro
Differential revision: https://reviews.freebsd.org/D36164

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protosw: retire pr_slowtimo and pr_fasttimo

They were useful many years ago, when the callwheel was not efficient,
and the kernel tried to have as little callout entries scheduled as
possible.

Revi

protosw: retire pr_slowtimo and pr_fasttimo

They were useful many years ago, when the callwheel was not efficient,
and the kernel tried to have as little callout entries scheduled as
possible.

Reviewed by: tuexen, melifaro
Differential revision: https://reviews.freebsd.org/D36163

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protosw: separate pr_input and pr_ctlinput out of protosw

The protosw KPI historically has implemented two quite orthogonal
things: protocols that implement a certain kind of socket, and
protocols t

protosw: separate pr_input and pr_ctlinput out of protosw

The protosw KPI historically has implemented two quite orthogonal
things: protocols that implement a certain kind of socket, and
protocols that are IPv4/IPv6 protocol. These two things do not
make one-to-one correspondence. The pr_input and pr_ctlinput methods
were utilized only in IP protocols. This strange duality required
IP protocols that doesn't have a socket to declare protosw, e.g.
carp(4). On the other hand developers of socket protocols thought
that they need to define pr_input/pr_ctlinput always, which lead to
strange dead code, e.g. div_input() or sdp_ctlinput().

With this change pr_input and pr_ctlinput as part of protosw disappear
and IPv4/IPv6 get their private single level protocol switch table
ip_protox[] and ip6_protox[] respectively, pointing at array of
ipproto_input_t functions. The pr_ctlinput that was used for
control input coming from the network (ICMP, ICMPv6) is now represented
by ip_ctlprotox[] and ip6_ctlprotox[].

ipproto_register() becomes the only official way to register in the
table. Those protocols that were always static and unlikely anybody
is interested in making them loadable, are now registered by ip_init(),
ip6_init(). An IP protocol that considers itself unloadable shall
register itself within its own private SYSINIT().

Reviewed by: tuexen, melifaro
Differential revision: https://reviews.freebsd.org/D36157

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ipsec: isolate knowledge about protocols that are last header

Retire PR_LASTHDR protosw flag.

Reviewed by: ae
Differential revision: https://reviews.freebsd.org/D36155

protosw: retire pr_output method

The only place to execute this method was raw_usend(). Only those
protocols that used raw socket were able to actually enter that method.
All pr_output assignments b

protosw: retire pr_output method

The only place to execute this method was raw_usend(). Only those
protocols that used raw socket were able to actually enter that method.
All pr_output assignments being deleted by this commit were a dead code
for many years.

Reviewed by: melifaro
Differential revision: https://reviews.freebsd.org/D36126

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sockets: use only soref()/sorele() as socket reference count

o Retire SS_FDREF as it is basically a debug flag on top of already
existing soref()/sorele().
o Convert SS_PROTOREF into soref()/sorel

sockets: use only soref()/sorele() as socket reference count

o Retire SS_FDREF as it is basically a debug flag on top of already
existing soref()/sorele().
o Convert SS_PROTOREF into soref()/sorele().
o Change reference model for the listen queues, see below.
o Make sofree() private. The correct KPI to use is only sorele().
o Make soabort() respect the model and sorele() instead of sofree().

Note on listening queues. Until now the sockets on a queue had zero
reference count. And the reference were given only upon accept(2). The
assumption was that there is no way to see the queued socket from anywhere
except its head. This is not true, since queued sockets already have pcbs,
which are linked at least into the global pcb lists. With this change we
put the reference right in the sonewconn() and on accept(2) path we just
hand the existing reference to the file descriptor.

Differential revision: https://reviews.freebsd.org/D35679

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sockets: use positive flag for file descriptor socket reference

Rename SS_NOFDREF to SS_FDREF and flip all bitwise operations.
Mark sockets created by socreate() with SS_FDREF.

This change is mostl

sockets: use positive flag for file descriptor socket reference

Rename SS_NOFDREF to SS_FDREF and flip all bitwise operations.
Mark sockets created by socreate() with SS_FDREF.

This change is mostly illustrative. With it we see that SS_FDREF
is a debugging flag, since:
* socreate() takes a reference with soref().
* on accept path solisten_dequeue() takes a reference
with soref() and then soaccept() sets SS_FDREF.
* soclose() checks SS_FDREF, removes it and does sorele().

Reviewed by: tuexen
Differential revision: https://reviews.freebsd.org/D35678

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sockbuf: remove unused mbuf counter and cluster counter

With M_EXTPG mbufs these two counters already do not represent the
reality. As we are moving towards protocol independent socket buffers,
whi

sockbuf: remove unused mbuf counter and cluster counter

With M_EXTPG mbufs these two counters already do not represent the
reality. As we are moving towards protocol independent socket buffers,
which may not even use mbufs at all, the counters become less and less
relevant. The only userland seeing them was 'netstat -x'.

PR: 264181 (exp-run)
Reviewed by: markj
Differential revision: https://reviews.freebsd.org/D35334

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domains: init with standard SYSINIT(9) or VNET_SYSINIT()

There left only three modules that used dom_init(). And netipsec
was the last one to use dom_destroy().

Differential revision: https://revi

domains: init with standard SYSINIT(9) or VNET_SYSINIT()

There left only three modules that used dom_init(). And netipsec
was the last one to use dom_destroy().

Differential revision: https://reviews.freebsd.org/D33540

show more ...

protocols: init with standard SYSINIT(9) or VNET_SYSINIT

The historical BSD network stack loop that rolls over domains and
over protocols has no advantages over more modern SYSINIT(9).
While doing t

protocols: init with standard SYSINIT(9) or VNET_SYSINIT

The historical BSD network stack loop that rolls over domains and
over protocols has no advantages over more modern SYSINIT(9).
While doing the sweep, split global and per-VNET initializers.

Getting rid of pr_init allows to achieve several things:
o Get rid of ifdef's that protect against double foo_init() when
both INET and INET6 are compiled in.
o Isolate initializers statically to the module they init.
o Makes code easier to understand and maintain.

Reviewed by: melifaro
Differential revision: https://reviews.freebsd.org/D33537

show more ...

net: attach IPv4 and IPv6 stacks to an interface with EVENTHANDLER(9)

This change retires two historic relics: the if_afdata[] array and the
dom_ifattach/dom_ifdetach methods.

The if_afdata[] array

net: attach IPv4 and IPv6 stacks to an interface with EVENTHANDLER(9)

This change retires two historic relics: the if_afdata[] array and the
dom_ifattach/dom_ifdetach methods.

The if_afdata[] array is a relic of the era, when there was expectation
that many transport protocols will coexist with IP, e.g. IPX or NetAtalk.
The array hasn't had any members except AF_INET and AF_INET6 for over a
decade already. This change removes the array and just leaves two pointer
fields: if_inet and if_inet6.

The dom_ifattach/dom_ifdetach predates the EVENTHANDLER(9) framework and
was a good enough method to initialize protocol contexts back then. Today
there is no good reason to treat IPv4 and IPv6 stacks differently to other
protocols/features that attach and detach from an interface.

The locking of if_afdata[] is a relic of SMPng times, when the system
startup and the interface attach was even more convoluted than before this
change, and we also had unloadable protocols that used a field in
if_afdata[]. Note that IPv4 and IPv6 are not unloadable.

Note that this change removes NET_EPOCH_WAIT() from the interface detach
sequence. This may surface several new races associated with interface
removal. I failed to hit any with consecutive test suite runs, though.
The expected general race scenario is that while struct ifnet is freed
with proper epoch_call(9) itself, some structures hanging off ifnet are
freed with direct free(9). The proper fix is either make if_foo point at
some static "dead" structure providing SMP visibility of this store, or
free those structure with epoch_call(9). All of these cases are planned
to be found and resolved during 16.0-CURRENT lifetime.

Reviewed by: zlei, gallatin, melifaro
Differential Revision: https://reviews.freebsd.org/D54089

show more ...

sockets: remove dom_externalize

It was used only by unix(4) and now is completely isolated.

sockets: garbage collect SB_NOINTR

Not used. All socket buffer sleeps are interruptible.

sockets: garbage collect SS_ISCONFIRMING

Fixes: 8df32b19dee92b5eaa4b488ae78dca6accfcb38e

sockets: remove dom_dispose and PR_RIGHTS

Passing file descriptors (rights) via sockets is a feature specific to
PF_UNIX only, so fully isolate the logic into uipc_usrreq.c.

Reviewed by: tuexen
Di

sockets: remove dom_dispose and PR_RIGHTS

Passing file descriptors (rights) via sockets is a feature specific to
PF_UNIX only, so fully isolate the logic into uipc_usrreq.c.

Reviewed by: tuexen
Differential Revision: https://reviews.freebsd.org/D43414

show more ...

sys: Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

show more ...