Commit Graph

213 Commits

Author SHA1 Message Date
Gleb Smirnoff
66dcee729c Garbage collect long time obsoleted (or never used) stuff from routing API. 2014-03-15 06:49:32 +00:00
Gleb Smirnoff
256ea2aba9 The route code used to mtx_destroy() a locked mutex before rtentry free. Now,
after r262763 it started to return locked mutexes to UMA. To fix that,
conditionally unlock the mutex in the destructor.

Tested by:	"Sergey V. Dyatko" <sergey.dyatko@gmail.com>
2014-03-05 21:16:46 +00:00
Gleb Smirnoff
e3a7aa6f56 - Remove rt_metrics_lite and simply put its members into rtentry.
- Use counter(9) for rt_pksent (former rt_rmx.rmx_pksent). This
  removes another cache trashing ++ from packet forwarding path.
- Create zini/fini methods for the rtentry UMA zone. Via initialize
  mutex and counter in them.
- Fix reporting of rmx_pksent to routing socket.
- Fix netstat(1) to report "Use" both in kvm(3) and sysctl(3) mode.

The change is mostly targeted for stable/10 merge. For head,
rt_pksent is expected to just disappear.

Discussed with:		melifaro
Sponsored by:		Netflix
Sponsored by:		Nginx, Inc.
2014-03-05 01:17:47 +00:00
George V. Neville-Neil
9b5f5ede41 Revert previous commit (262727) and bounce patch back to the
submitter.

Pointed out by: jhb
2014-03-04 23:55:04 +00:00
George V. Neville-Neil
596031c052 Naming consistency fix. The routing code defines
RADIX_NODE_HEAD_LOCK as grabbing the write lock,
but RADIX_NODE_HEAD_LOCK_ASSERT as checking the read lock.

Submitted by:	Vijay Singh <vijju.singh at gmail.com>
MFC after:	1 month
2014-03-04 05:09:46 +00:00
Gleb Smirnoff
5d6d7e756b o Revamp API between flowtable and netinet, netinet6.
- ip_output() and ip_output6() simply call flowtable_lookup(),
    passing mbuf and address family. That's the only code under
    #ifdef FLOWTABLE in the protocols code now.
o Revamp statistics gathering and export.
  - Remove hand made pcpu stats, and utilize counter(9).
  - Snapshot of statistics is available via 'netstat -rs'.
  - All sysctls are moved into net.flowtable namespace, since
    spreading them over net.inet isn't correct.
o Properly separate at compile time INET and INET6 parts.
o General cleanup.
  - Remove chain of multiple flowtables. We simply have one for
    IPv4 and one for IPv6.
  - Flowtables are allocated in flowtable.c, symbols are static.
  - With proper argument to SYSINIT() we no longer need flowtable_ready.
  - Hash salt doesn't need to be per-VNET.
  - Removed rudimentary debugging, which use quite useless in dtrace era.

The runtime behavior of flowtable shouldn't be changed by this commit.

Sponsored by:	Netflix
Sponsored by:	Nginx, Inc.
2014-02-07 15:18:23 +00:00
Alexander V. Chernikov
d375edc9b5 Simplify inet alias handling code: if we're adding/removing alias which
has the same prefix as some other alias on the same interface, use
newly-added rt_addrmsg() instead of hand-rolled in_addralias_rtmsg().

This eliminates the following rtsock messages:

Pinned RTM_ADD for prefix (for alias addition).
Pinned RTM_DELETE for prefix (for alias withdrawal).

Example (got 10.0.0.1/24 on vlan4, playing with 10.0.0.2/24):

before commit, addition:

  got message of size 116 on Fri Jan 10 14:13:15 2014
  RTM_NEWADDR: address being added to iface: len 116, metric 0, flags:
  sockaddrs: <NETMASK,IFP,IFA,BRD>
   255.255.255.0 vlan4:8.0.27.c5.29.d4 10.0.0.2 10.0.0.255

  got message of size 192 on Fri Jan 10 14:13:15 2014
  RTM_ADD: Add Route: len 192, pid: 0, seq 0, errno 0, flags:<UP,PINNED>
  locks:  inits:
  sockaddrs: <DST,GATEWAY,NETMASK>
   10.0.0.0 10.0.0.2 (255) ffff ffff ff

after commit, addition:

  got message of size 116 on Fri Jan 10 13:56:26 2014
  RTM_NEWADDR: address being added to iface: len 116, metric 0, flags:
  sockaddrs: <NETMASK,IFP,IFA,BRD>
   255.255.255.0 vlan4:8.0.27.c5.29.d4 14.0.0.2 14.0.0.255

before commit, wihdrawal:

  got message of size 192 on Fri Jan 10 13:58:59 2014
  RTM_DELETE: Delete Route: len 192, pid: 0, seq 0, errno 0, flags:<UP,PINNED>
  locks:  inits:
  sockaddrs: <DST,GATEWAY,NETMASK>
   10.0.0.0 10.0.0.2 (255) ffff ffff ff

  got message of size 116 on Fri Jan 10 13:58:59 2014
  RTM_DELADDR: address being removed from iface: len 116, metric 0, flags:
  sockaddrs: <NETMASK,IFP,IFA,BRD>
   255.255.255.0 vlan4:8.0.27.c5.29.d4 10.0.0.2 10.0.0.255

adter commit, withdrawal:

  got message of size 116 on Fri Jan 10 14:14:11 2014
  RTM_DELADDR: address being removed from iface: len 116, metric 0, flags:
  sockaddrs: <NETMASK,IFP,IFA,BRD>
   255.255.255.0 vlan4:8.0.27.c5.29.d4 10.0.0.2 10.0.0.255

Sending both RTM_ADD/RTM_DELETE messages to rtsock is completely wrong
(and requires some hacks to keep prefix in route table on RTM_DELETE).

I've tested this change with quagga (no change) and bird (*).

bird alias handling is already broken in *BSD sysdep code, so nothing
changes here, too.

I'm going to MFC this change if there will be no complains about behavior
change.

While here, fix some style(9) bugs introduced by r260488
(pointed by glebius and bde).

Sponsored by:	Yandex LLC
MFC after:	4 weeks
2014-01-10 12:13:55 +00:00
Alexander V. Chernikov
4cbac30b29 Split rt_newaddrmsg_fib() into two different functions.
Adding/deleting interface addresses involves access to 3 different subsystems,
int different parts of code. Each call can fail, so reporting successful
operation by rtsock in the middle of the process error-prone.

Further split routing notification API and actual rtsock calls via creating
public-available rt_addrmsg() / rt_routemsg() functions with "private"
rtsock_* backend.

MFC after:	2 weeks
2014-01-09 18:13:25 +00:00
Alexander V. Chernikov
7d9b6df18b Constanly use RT_ALL_FIBS everywhere instead of -1.
MFC after:	2 weeks
2014-01-08 23:09:02 +00:00
Alexander V. Chernikov
034c09ff10 Partially fix IPv4 interface routes deletion in RADIX_MPATH.
Noticed by:	Nikolay Denev <ndenev at gmail.com>
MFC after:	1 month
2014-01-06 22:36:20 +00:00
Alexander V. Chernikov
5a2f4cbd92 Change semantics for rnh_lookup() function: now
it performs exact match search, regardless of netmask existance.
This simplifies most of rnh_lookup() consumers.

Fix panic triggered by deleting non-existent host route.

PR:		kern/185092
Submitted by:	Nikolay Denev <ndenev at gmail.com>
MFC after:	1 month
2014-01-04 22:25:26 +00:00
Craig Rodrigues
6274ce3e2b In vnet_route_uninit(), free some memory that is allocated in vnet_route_init().
To reproduce the problem:
  (1)  Take a GENERIC kernel config, and add options for: VIMAGE, WITNESS,
       INVARIANTS.
  (2)  Run this command in a loop:
       jail -l -u root -c path=/ name=foo persist vnet && jexec foo ifconfig lo0 127.0.0.1/8 && jail -r foo

       see: http://lists.freebsd.org/pipermail/freebsd-current/2010-November/021280.html
            http://lists.freebsd.org/pipermail/freebsd-current/2010-November/021291.html

This doesn't eliminate all the "Freed UMA keg was not empty" warning messages
on the console, but it helps.
2013-11-25 20:33:33 +00:00
Gleb Smirnoff
76039bc84f The r48589 promised to remove implicit inclusion of if_var.h soon. Prepare
to this event, adding if_var.h to files that do need it. Also, include
all includes that now are included due to implicit pollution via if_var.h

Sponsored by:	Netflix
Sponsored by:	Nginx, Inc.
2013-10-26 17:58:36 +00:00
Alexander V. Chernikov
65a17d744e Fix long-standing issue with incorrect radix mask calculation.
Usual symptoms are messages like
rn_delete: inconsistent annotation
rn_addmask: mask impossibly already in tree
or inability to flush/delete particular prefix in ipfw table.

Changes:
* Assume 32 bytes as maximum radix key length
* Remove rn_init()
* Statically allocate rn_ones/rn_zeroes
* Make separate mask tree for each "normal" tree instead of system global one
* Remove "optimization" on masks reusage and key zeroying
* Change rn_addmask() arguments to accept tree pointer (no users in base)

PR:		kern/182851, kern/169206, kern/135476, kern/134531
Found by:	Slawa Olhovchenkov <slw@zxy.spb.ru>
MFC after:	2 weeks
Reviewed by:	glebius
Sponsored by:	Yandex LLC
2013-10-16 12:18:44 +00:00
Alexander V. Chernikov
d54455b0c9 Fix rte leak introduced in r248070.
MFC after:	2 weeks
2013-05-18 07:10:22 +00:00
Julian Elischer
4871fc4ab5 Finally change the mbuf to have its own fib field instead of stealing
4 flag bits. This was supposed to happen in 8.0, and again in 2012..

MFC after:	never
2013-05-16 16:20:17 +00:00
Alexander V. Chernikov
3034f43f2f Fix long-standing issue with interface routes being unprotected:
Use RTM_PINNED flag to mark route as immutable.
Forbid deleting immutable routes without special rtrequest1_fib() flag.
Adding interface address with prefix already in route table is handled
by atomically deleting old prefix and adding interface one.

Discussed with:	andre, eri
MFC after:	3 weeks
2013-03-08 20:33:50 +00:00
Alexander V. Chernikov
14126522cf Write lock is not required for find&compare operation.
MFC after:	2 weeks
2013-03-05 13:38:45 +00:00
Bjoern A. Zeeb
bfca216eb9 Hide kernel option ROUTETABLES evaluations in the implementation
rather than the header file.  With this also move RT_MAXFIBS and
RT_NUMFIBS into the implemantion to avoid further usage in other
code. rt_numfibs is all that should be needed.

This allows users to change the number of FIBs from 1..RT_MAXFIBS(16)
dynamically using the tunable without the need to change the kernel
config for the maximum anymore.  This means that thet multi-FIB
feature is now fully available with GENERIC kernels.
The kernel option ROUTETABLES can still be used to set the default
numbers of FIBs in absence of the tunable.

Ok.ed by:	julian, hrs, melifaro
MFC after:	2 weeks
2012-03-18 11:23:40 +00:00
Bjoern A. Zeeb
a84986256f Move a comment from rtinit1() to the top of the file where dealing with
the (maximum) number of FIBs trying to clarify that evetually FIBs
should probably attached to domain(9) specific storage. [1]

Add a comment on a limitimation on the rt_add_addr_allfibs option.

Use RT_DEFAULT_FIB instead of 0 where applicable.

Add empty line to functions without local variables per style.

Put public yet unused in-tree function rtinit_fib() under BURN_BRIDGES
to indicate that it might go away in the future.

No functional change.

Discussed with:	julian [1] (clarification on what the original one meant)
Sponsored by:	Cisco Systems, Inc.
2012-02-03 12:25:14 +00:00
Bjoern A. Zeeb
b3dd077152 Minor optimization doing input validation with a possible early return
before doing further work.

Sponsored by:	Cisco Systems, Inc.
2012-02-03 11:20:11 +00:00
Bjoern A. Zeeb
096f27864f Fix FLOWTABLE IPv6 handling in route.c missed in r205066.
While doing so, for consistency with the rtalloc_ign_fib(9) interface
called, remove the "in_" prefix from rtalloc_ign_wrapper() no longer
indicating that it would only handle the INET case.

Sponsored by:	Cisco Systems, Inc.
2012-02-03 10:17:34 +00:00
Bjoern A. Zeeb
b680a383a8 Allow for IPv6 to allocate (and in the VIMAGE case free) as many routing
tables (FIBs) as IPv4.
Prepare various general rt* functions for multi-FIB IPv6 handling in
addition to already existing multi-FIB IPv4 cases.

Sponsored by:	Cisco Systems, Inc.
2012-02-03 09:23:55 +00:00
Bjoern A. Zeeb
8d74af3668 Replace random ARIN direct assignment legacy IPs with proper RFC 5735
TEST-NET1 block for use in documentation and example code addresses.

MFC after:	3 days
2012-01-24 15:20:31 +00:00
Gleb Smirnoff
f3909e37ff Simplify rtrequest(RTM_ADD): ifa can't be NULL after rt_getifa_fib(). 2011-12-15 12:49:10 +00:00
Qing Li
46a70de2b0 The host-id/interface-id can have a specific value and is properly
masked out when adding a prefix route through the "route" command.
However, when deleting the route, simply changing the command keyword
from "add" to "delete" does not work. The failoure is observed in
both IPv4 and IPv6 route insertion. The patch makes the route command
behavior consistent between the "add" and the "delete" operation.

MFC after:	1 week
2011-10-25 00:34:39 +00:00
Bjoern A. Zeeb
528737fdfe Pass the fibnum where we need filtering of the message on the
rtsock allowing routing daemons to filter routing updates on an
rtsock per FIB.

Adjust raw_input() and split it into wrapper and a new function
taking an optional callback argument even though we only have one
consumer [1] to keep the hackish flags local to rtsock.c.

PR:		kern/134931
Submitted by:	multiple (see PR)
Suggested by:	rwatson [1]
Reviewed by:	rwatson
MFC after:	3 days
2011-09-28 13:48:36 +00:00
Kip Macy
8451d0dd78 In order to maximize the re-usability of kernel code in user space this
patch modifies makesyscalls.sh to prefix all of the non-compatibility
calls (e.g. not linux_, freebsd32_) with sys_ and updates the kernel
entry points and all places in the code that use them. It also
fixes an additional name space collision between the kernel function
psignal and the libc function of the same name by renaming the kernel
psignal kern_psignal(). By introducing this change now we will ease future
MFCs that change syscalls.

Reviewed by:	rwatson
Approved by:	re (bz)
2011-09-16 13:58:51 +00:00
Kevin Lo
e9ff3d45e4 In rtinit1(), before rtrequest1_fib() is called, info.rti_flags is
initialized by flags (function argument) or-ed with ifa->ifa_flags.
If both NIC has a loopback route to itself, so IFA_RTSELF is set on ifa(s).
As IFA_RTSELF is defined by RTF_HOST, rtrequest1_fib() is called with
RTF_HOST flag even if netmask is not NULL. Consequently, netmask is set
to zero in rtrequest1_fib(), and request to add network route is changed
under hands to request to add host route.

Tested by:	Andrew Boyer <aboyer at averesystems.com>
Submitted by:	Svatopluk Kraus <onwahe at gmail dot com>
Approved by:	re (hrs)
2011-08-08 05:25:51 +00:00
Bjoern A. Zeeb
f5857e2d3d Garbage collect never used global, sysctl, externs.
MFC after:	1 week
2011-06-21 07:19:03 +00:00
Bjoern A. Zeeb
b8b8e0c981 Leave an extra comment about flowtable and IPv6 support rectifying a
previous comment.

MFC after:	1 week
2011-06-20 12:35:12 +00:00
Dmitry Chagin
e579f1c1cf ouch, newrt is used on the return path, my fault.
Partialy revert the previous change.

MFC after:	1 Week.
2011-03-19 21:10:57 +00:00
Dmitry Chagin
523e60025b A bit rearranged rtalloc1_fib() code.
Initialize a variable when it is really needed.
To avoid code duplication move the miss label to line up and jump on it.

MFC after:	1 Week
2011-03-19 19:50:36 +00:00
Dmitry Chagin
6a873ef717 Remove a now unused variable.
MFC after:	1 Week
2011-03-19 16:52:06 +00:00
Rebecca Cran
6bccea7c2b Fix typos - remove duplicate "the".
PR:	bin/154928
Submitted by:	Eitan Adler <lists at eitanadler.com>
MFC after: 	3 days
2011-02-21 09:01:34 +00:00
Matthew D Fleming
f88910cdf5 sysctl(9) cleanup checkpoint: amd64 GENERIC builds cleanly.
Commit the net* piece.
2011-01-12 19:53:50 +00:00
Dimitry Andric
3e288e6238 After some off-list discussion, revert a number of changes to the
DPCPU_DEFINE and VNET_DEFINE macros, as these cause problems for various
people working on the affected files.  A better long-term solution is
still being considered.  This reversal may give some modules empty
set_pcpu or set_vnet sections, but these are harmless.

Changes reverted:

------------------------------------------------------------------------
r215318 | dim | 2010-11-14 21:40:55 +0100 (Sun, 14 Nov 2010) | 4 lines

Instead of unconditionally emitting .globl's for the __start_set_xxx and
__stop_set_xxx symbols, only emit them when the set_vnet or set_pcpu
sections are actually defined.

------------------------------------------------------------------------
r215317 | dim | 2010-11-14 21:38:11 +0100 (Sun, 14 Nov 2010) | 3 lines

Apply the STATIC_VNET_DEFINE and STATIC_DPCPU_DEFINE macros throughout
the tree.

------------------------------------------------------------------------
r215316 | dim | 2010-11-14 21:23:02 +0100 (Sun, 14 Nov 2010) | 2 lines

Add macros to define static instances of VNET_DEFINE and DPCPU_DEFINE.
2010-11-22 19:32:54 +00:00
Dimitry Andric
31c6a0037e Apply the STATIC_VNET_DEFINE and STATIC_DPCPU_DEFINE macros throughout
the tree.
2010-11-14 20:38:11 +00:00
Qing Li
0ed6142b31 This patch fixes the problem where proxy ARP entries cannot be added
over the if_ng interface.

MFC after:	3 days
2010-05-25 20:42:35 +00:00
Bjoern A. Zeeb
82cea7e6f3 MFP4: @176978-176982, 176984, 176990-176994, 177441
"Whitspace" churn after the VIMAGE/VNET whirls.

Remove the need for some "init" functions within the network
stack, like pim6_init(), icmp_init() or significantly shorten
others like ip6_init() and nd6_init(), using static initialization
again where possible and formerly missed.

Move (most) variables back to the place they used to be before the
container structs and VIMAGE_GLOABLS (before r185088) and try to
reduce the diff to stable/7 and earlier as good as possible,
to help out-of-tree consumers to update from 6.x or 7.x to 8 or 9.

This also removes some header file pollution for putatively
static global variables.

Revert VIMAGE specific changes in ipfilter::ip_auth.c, that are
no longer needed.

Reviewed by:	jhb
Discussed with:	rwatson
Sponsored by:	The FreeBSD Foundation
Sponsored by:	CK Software GmbH
MFC after:	6 days
2010-04-29 11:52:42 +00:00
Qing Li
c7ea0aa648 One of the advantages of enabling ECMP (a.k.a RADIX_MPATH) is to
allow for connection load balancing across interfaces. Currently
the address alias handling method is colliding with the ECMP code.
For example, when two interfaces are configured on the same prefix,
only one prefix route is installed. So connection load balancing
among the available interfaces is not possible.

The other advantage of ECMP is for failover. The issue with the
current code, is that the interface link-state is not reflected
in the route entry. For example, if there are two interfaces on
the same prefix, the cable on one interface is unplugged, new and
existing connections should switch over to the other interface.
This is not done today and packets go into a black hole.

Also, there is a small bug in the kernel where deleting ECMP routes
in the userland will always return an error even though the command
is successfully executed.

MFC after:	5 days
2010-03-09 01:11:45 +00:00
Qing Li
c7ab66020f The proxy arp entries could not be added into the system over the
IFF_POINTOPOINT link types. The reason was due to the routing
entry returned from the kernel covering the remote end is of an
interface type that does not support ARP. This patch fixes this
problem by providing a hint to the kernel routing code, which
indicates the prefix route instead of the PPP host route should
be returned to the caller. Since a host route to the local end
point is also added into the routing table, and there could be
multiple such instantiations due to multiple PPP links can be
created with the same local end IP address, this patch also fixes
the loopback route installation failure problem observed prior to
this patch. The reference count of loopback route to local end would
be either incremented or decremented. The first instantiation would
create the entry and the last removal would delete the route entry.

MFC after:	5 days
2009-12-30 21:35:34 +00:00
Luigi Rizzo
614cb83990 Move the scan for max_keylen into route.c::route_init(),
and make max_keylen an argument for rn_init().
This removes an unnecessary dependency on domain.h from radix.c

MFC after:	7 days
2009-12-14 20:12:51 +00:00
Michael Tuexen
7f2797200f Fix a LOR showing up with sctp_bsd_addr(): Do not hold a rt lock
when calling rt_newaddrmsg().

Reviewed by: qingli
Approved by: rrs (mentor)
MFC after: 1 month
2009-11-17 12:57:10 +00:00
Bjoern A. Zeeb
db44ff4047 Put #ifdef INET around parts of the FLOWTABLE code, to unbreak
nooptions INET kernel builds.

MFC after:	3 days
X-MFC:		with r197687
2009-10-03 10:56:03 +00:00
Qing Li
e5c610d659 The flow-table associates TCP/UDP flows and IP destinations with
specific routes. When the routing table changes, for example,
when a new route with a more specific prefix is inserted into the
routing table, the flow-table is not updated to reflect that change.
As such existing connections cannot take advantage of the new path.
In some cases the path is broken. This patch will update the affected
flow-table entries when a more specific route is added. The route
entry is properly marked when a route is deleted from the table.
In this case, when the flow-table performs a search, the stale
entry is updated automatically. Therefore this patch is not
necessary for route deletion.

Submitted by:	simon, phk
Reviewed by:	bz, kmacy
MFC after:	3 days
2009-10-01 20:32:29 +00:00
Robert Watson
530c006014 Merge the remainder of kern_vimage.c and vimage.h into vnet.c and
vnet.h, we now use jails (rather than vimages) as the abstraction
for virtualization management, and what remained was specific to
virtual network stacks.  Minor cleanups are done in the process,
and comments updated to reflect these changes.

Reviewed by:	bz
Approved by:	re (vimage blanket)
2009-08-01 19:26:27 +00:00
Robert Watson
d0728d7174 Introduce and use a sysinit-based initialization scheme for virtual
network stacks, VNET_SYSINIT:

- Add VNET_SYSINIT and VNET_SYSUNINIT macros to declare events that will
  occur each time a network stack is instantiated and destroyed.  In the
  !VIMAGE case, these are simply mapped into regular SYSINIT/SYSUNINIT.
  For the VIMAGE case, we instead use SYSINIT's to track their order and
  properties on registration, using them for each vnet when created/
  destroyed, or immediately on module load for already-started vnets.
- Remove vnet_modinfo mechanism that existed to serve this purpose
  previously, as well as its dependency scheme: we now just use the
  SYSINIT ordering scheme.
- Implement VNET_DOMAIN_SET() to allow protocol domains to declare that
  they want init functions to be called for each virtual network stack
  rather than just once at boot, compiling down to DOMAIN_SET() in the
  non-VIMAGE case.
- Walk all virtualized kernel subsystems and make use of these instead
  of modinfo or DOMAIN_SET() for init/uninit events.  In some cases,
  convert modular components from using modevent to using sysinit (where
  appropriate).  In some cases, do minor rejuggling of SYSINIT ordering
  to make room for or better manage events.

Portions submitted by:	jhb (VNET_SYSINIT), bz (cleanup)
Discussed with:		jhb, bz, julian, zec
Reviewed by:		bz
Approved by:		re (VIMAGE blanket)
2009-07-23 20:46:49 +00:00
Robert Watson
1e77c1056a Remove unused VNET_SET() and related macros; only VNET_GET() is
ever actually used.  Rename VNET_GET() to VNET() to shorten
variable references.

Discussed with:	bz, julian
Reviewed by:	bz
Approved by:	re (kensmith, kib)
2009-07-16 21:13:04 +00:00
Robert Watson
eddfbb763d Build on Jeff Roberson's linker-set based dynamic per-CPU allocator
(DPCPU), as suggested by Peter Wemm, and implement a new per-virtual
network stack memory allocator.  Modify vnet to use the allocator
instead of monolithic global container structures (vinet, ...).  This
change solves many binary compatibility problems associated with
VIMAGE, and restores ELF symbols for virtualized global variables.

Each virtualized global variable exists as a "reference copy", and also
once per virtual network stack.  Virtualized global variables are
tagged at compile-time, placing the in a special linker set, which is
loaded into a contiguous region of kernel memory.  Virtualized global
variables in the base kernel are linked as normal, but those in modules
are copied and relocated to a reserved portion of the kernel's vnet
region with the help of a the kernel linker.

Virtualized global variables exist in per-vnet memory set up when the
network stack instance is created, and are initialized statically from
the reference copy.  Run-time access occurs via an accessor macro, which
converts from the current vnet and requested symbol to a per-vnet
address.  When "options VIMAGE" is not compiled into the kernel, normal
global ELF symbols will be used instead and indirection is avoided.

This change restores static initialization for network stack global
variables, restores support for non-global symbols and types, eliminates
the need for many subsystem constructors, eliminates large per-subsystem
structures that caused many binary compatibility issues both for
monitoring applications (netstat) and kernel modules, removes the
per-function INIT_VNET_*() macros throughout the stack, eliminates the
need for vnet_symmap ksym(2) munging, and eliminates duplicate
definitions of virtualized globals under VIMAGE_GLOBALS.

Bump __FreeBSD_version and update UPDATING.

Portions submitted by:  bz
Reviewed by:            bz, zec
Discussed with:         gnn, jamie, jeff, jhb, julian, sam
Suggested by:           peter
Approved by:            re (kensmith)
2009-07-14 22:48:30 +00:00