Commit Graph

357 Commits

Author SHA1 Message Date
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
Gleb Smirnoff
2a7da7299d Remove ifa_ref()/ifa_free(), which are atomic(9), from ip_output().
The ifaddr is already referenced by the rtentry, and we are holding
reference on the rtentry throughout the function execution.

Sponsored by:	Netflix
Sponsored by:	Nginx, Inc.
2014-03-04 19:49:41 +00:00
Gleb Smirnoff
0ff96b4f55 o Remove at compile time the HASH_ALL code, that was never
tested and is unfinished. However, I've tested my version,
  it works okay. As before it is unfinished: timeout aren't
  driven by TCP session state. To enable the HASH_ALL mode,
  one needs in kernel config:

	options FLOWTABLE_HASH_ALL

o Reduce the alignment on flentry to 64 bytes. Without
  the FLOWTABLE_HASH_ALL option, twice less memory would
  be consumed by flows.
o API to ip_output()/ip6_output() got even more thin: 1 liner.
o Remove unused unions. Simply use fle->f_key[].
o Merge all IPv4 code into flowtable_lookup_ipv4(), and do same
  flowtable_lookup_ipv6(). Stop copying data to on stack
  sockaddr structures, simply use key[] on stack.
o Move code from flowtable_lookup_common() that actually works
  on insertion into flowtable_insert().

Sponsored by:	Netflix
Sponsored by:	Nginx, Inc.
2014-02-17 11:50:56 +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
Gleb Smirnoff
3c065f2f3e Cleanup comments and whitespace. No functional changes. 2014-01-16 12:58:03 +00:00
Alexander V. Chernikov
054692a4bd Fix ipfw fwd for IPv4 traffic broken by r249894.
Problem case:
Original lookup returns route with GW set, so gw points to
rte->rt_gateway.
After that we're changing dst and performing lookup another time.
Since fwd host is most probably directly reachable, resulting
rte does not contain rt_gateway, so gw is not set. Finally, we
end with packet transmitted to proper interface but wrong
link-layer address.

Found by:	lstewart
Discussed with:	ae,lstewart
MFC after:	2 weeks
Sponsored by:	Yandex LLC
2014-01-16 11:50:00 +00:00
Gleb Smirnoff
183e1c8634 Fix regression from r249894. Now we pass "gw" as argument to if_output
method, thus for multicast case we need it to point at "dst".

PR:		185395
Submitted by:	ae
2014-01-02 10:18:39 +00:00
Adrian Chadd
ac7e121247 Disable the now unpredicably bogus check for whether we have
eneough queue space before queuing a bunch of IP fragments.

As the comment in the committed change says, in the post-if_transmit(),
post-SMP, post-preemption world, there's just too much overlapping
concurrent code paths and different approaches to driver transmit
queue management to have this code even remotely be effective.

The only specific place it could be useful is if ALTQ is enabled
but again it doesn't at all promise that all the fragments will be
transmitted anyway.

The main reason for committing this change is to disable a parallel
place where the drops counter is incremented.  This is a side effect
of an upcoming change to ixgbe/cxgbe to handle the queue drops
counter slightly better.

Sponsored by:	Netflix, Inc.
2013-12-20 07:41:03 +00:00
Attilio Rao
54366c0bd7 - For kernel compiled only with KDTRACE_HOOKS and not any lock debugging
option, unbreak the lock tracing release semantic by embedding
  calls to LOCKSTAT_PROFILE_RELEASE_LOCK() direclty in the inlined
  version of the releasing functions for mutex, rwlock and sxlock.
  Failing to do so skips the lockstat_probe_func invokation for
  unlocking.
- As part of the LOCKSTAT support is inlined in mutex operation, for
  kernel compiled without lock debugging options, potentially every
  consumer must be compiled including opt_kdtrace.h.
  Fix this by moving KDTRACE_HOOKS into opt_global.h and remove the
  dependency by opt_kdtrace.h for all files, as now only KDTRACE_FRAMES
  is linked there and it is only used as a compile-time stub [0].

[0] immediately shows some new bug as DTRACE-derived support for debug
in sfxge is broken and it was never really tested.  As it was not
including correctly opt_kdtrace.h before it was never enabled so it
was kept broken for a while.  Fix this by using a protection stub,
leaving sfxge driver authors the responsibility for fixing it
appropriately [1].

Sponsored by:	EMC / Isilon storage division
Discussed with:	rstone
[0] Reported by:	rstone
[1] Discussed with:	philip
2013-11-25 07:38:45 +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
Gleb Smirnoff
7caf4ab7ac - Utilize counter(9) to accumulate statistics on interface addresses. Add
four counters to struct ifaddr. This kills '+=' on a variables shared
  between processors for every packet.
- Nuke struct if_data from struct ifaddr.
- In ip_input() do not put a reference on ifaddr, instead update statistics
  right now in place and do IN_IFADDR_RUNLOCK(). These removes atomic(9)
  for every packet. [1]
- To properly support NET_RT_IFLISTL sysctl used by getifaddrs(3), in
  rtsock.c fill if_data fields using counter_u64_fetch().
- Accidentially fix bug in COMPAT_32 version of NET_RT_IFLISTL, which
  took if_data not from the ifaddr, but from ifaddr's ifnet. [2]

Submitted by:	melifaro [1], pluknet[2]
Sponsored by:	Netflix
Sponsored by:	Nginx, Inc.
2013-10-15 11:37:57 +00:00
Mark Johnston
57f6086735 Implement the ip, tcp, and udp DTrace providers. The probe definitions use
dynamic translation so that their arguments match the definitions for
these providers in Solaris and illumos. Thus, existing scripts for these
providers should work unmodified on FreeBSD.

Tested by:	gnn, hiren
MFC after:	1 month
2013-08-25 21:54:41 +00:00
Andre Oppermann
86bd049144 Add m_clrprotoflags() to clear protocol specific mbuf flags at up and
downwards layer crossings.

Consistently use it within IP, IPv6 and ethernet protocols.

Discussed with:	trociny, glebius
2013-08-19 13:27:32 +00:00
Andre Oppermann
fb86dfcd2f Remove unused M_FRAG, M_FIRSTFRAG and M_LASTFRAG tagging from ip_fragment().
There wasn't any real driver (and hardware) support for it.  Modern hardware
does full fragmentation/segmentation offload instead.
2013-08-19 10:30:15 +00:00
Mikolaj Golub
efdf104bca In r227207, to fix the issue with possible NULL inp_socket pointer
dereferencing, when checking for SO_REUSEPORT option (and SO_REUSEADDR
for multicast), INP_REUSEPORT flag was introduced to cache the socket
option.  It was decided then that one flag would be enough to cache
both SO_REUSEPORT and SO_REUSEADDR: when processing SO_REUSEADDR
setsockopt(2), it was checked if it was called for a multicast address
and INP_REUSEPORT was set accordingly.

Unfortunately that approach does not work when setsockopt(2) is called
before binding to a multicast address: the multicast check fails and
INP_REUSEPORT is not set.

Fix this by adding INP_REUSEADDR flag to unconditionally cache
SO_REUSEADDR.

PR:		179901
Submitted by:	Michael Gmelin freebsd grem.de (initial version)
Reviewed by:	rwatson
MFC after:	1 week
2013-07-04 18:38:00 +00:00
Gleb Smirnoff
47e8d432d5 Add const qualifier to the dst parameter of the ifnet if_output method. 2013-04-26 12:50:32 +00:00
Gleb Smirnoff
4c7a605968 Introduce a pointer to const variable gw, which points either at the
same place as dst, or to the sockaddr in the routing table.

The const constraint of gw makes us safe from modifing routing table
accidentially. And "onstantness" of dst allows us to remove several
bandaids, when we switched it back at &ro->ro_dst, now it always
points there.

Reviewed by:	rrs
2013-04-25 12:42:09 +00:00
Randall Stewart
0be23a54cf This fixes the issue with the "randomly changing" default
route. What it was is there are two places in ip_output.c
where we do a goto again. One place was fine, it
copies out the new address and then resets dst = ro->rt_dst;
But the other place does *not* do that, which means earlier
when we found the gateway, we have dst pointing there
aka dst = ro->rt_gateway is done.. then we do a
goto again.. bam now we clobber the default route.

The fix is just to move the again so we are always
doing dst = &ro->rt_dst; in the again loop.

PR:	 174749,157796
MFC after:	1 week
2013-04-24 18:30:32 +00:00
Gleb Smirnoff
dc4ad05ecd Use m_get/m_gethdr instead of compat macros.
Sponsored by:	Nginx, Inc.
2013-03-15 12:55:30 +00:00
Gleb Smirnoff
eb1b1807af Mechanically substitute flags from historic mbuf allocator with
malloc(9) flags within sys.

Exceptions:

- sys/contrib not touched
- sys/mbuf.h edited manually
2012-12-05 08:04:20 +00:00
Andre Oppermann
da2299c5c7 Remove unused and unnecessary CSUM_IP_FRAGS checksumming capability.
Checksumming the IP header of fragments is no different from doing
normal IP headers.

Discussed with:	yongari
MFC after:	1 week
2012-11-27 19:31:49 +00:00
Andrey V. Elsukov
ffdbf9da3b Remove the recently added sysctl variable net.pfil.forward.
Instead, add protocol specific mbuf flags M_IP_NEXTHOP and
M_IP6_NEXTHOP. Use them to indicate that the mbuf's chain
contains the PACKET_TAG_IPFORWARD tag. And do a tag lookup
only when this flag is set.

Suggested by:	andre
2012-11-02 01:20:55 +00:00
Gleb Smirnoff
078468ede4 o Remove last argument to ip_fragment(), and obtain all needed information
on checksums directly from mbuf flags. This simplifies code.
o Clear CSUM_IP from the mbuf in ip_fragment() if we did checksums in
  hardware. Some driver may not announce CSUM_IP in theur if_hwassist,
  although try to do checksums if CSUM_IP set on mbuf. Example is em(4).
o While here, consistently use CSUM_IP instead of its alias CSUM_DELAY_IP.
  After this change CSUM_DELAY_IP vanishes from the stack.

Submitted by:	Sebastian Kuzminsky <seb lineratesystems.com>
2012-10-26 21:06:33 +00:00
Andrey V. Elsukov
c1de64a495 Remove the IPFIREWALL_FORWARD kernel option and make possible to turn
on the related functionality in the runtime via the sysctl variable
net.pfil.forward. It is turned off by default.

Sponsored by:	Yandex LLC
Discussed with:	net@
MFC after:	2 weeks
2012-10-25 09:39:14 +00:00
Gleb Smirnoff
8f134647ca Switch the entire IPv4 stack to keep the IP packet header
in network byte order. Any host byte order processing is
done in local variables and host byte order values are
never[1] written to a packet.

  After this change a packet processed by the stack isn't
modified at all[2] except for TTL.

  After this change a network stack hacker doesn't need to
scratch his head trying to figure out what is the byte order
at the given place in the stack.

[1] One exception still remains. The raw sockets convert host
byte order before pass a packet to an application. Probably
this would remain for ages for compatibility.

[2] The ip_input() still subtructs header len from ip->ip_len,
but this is planned to be fixed soon.

Reviewed by:	luigi, Maxim Dounin <mdounin mdounin.ru>
Tested by:	ray, Olivier Cochard-Labbe <olivier cochard.me>
2012-10-22 21:09:03 +00:00
Gleb Smirnoff
347d90acff Fix a miss from r241344: in ip_mloopback() we need to go to
net byte order prior to calling in_delayed_cksum().

Reported by:	 Olivier Cochard-Labbe <olivier cochard.me>
2012-10-14 15:08:07 +00:00
Gleb Smirnoff
23e9c6dc1e After r241245 it appeared that in_delayed_cksum(), which still expects
host byte order, was sometimes called with net byte order. Since we are
moving towards net byte order throughout the stack, the function was
converted to expect net byte order, and its consumers fixed appropriately:
  - ip_output(), ipfilter(4) not changed, since already call
    in_delayed_cksum() with header in net byte order.
  - divert(4), ng_nat(4), ipfw_nat(4) now don't need to swap byte order
    there and back.
  - mrouting code and IPv6 ipsec now need to switch byte order there and
    back, but I hope, this is temporary solution.
  - In ipsec(4) shifted switch to net byte order prior to in_delayed_cksum().
  - pf_route() catches up on r241245 changes to ip_output().
2012-10-08 08:03:58 +00:00
Gleb Smirnoff
21d172a3f1 A step in resolving mess with byte ordering for AF_INET. After this change:
- All packets in NETISR_IP queue are in net byte order.
  - ip_input() is entered in net byte order and converts packet
    to host byte order right _after_ processing pfil(9) hooks.
  - ip_output() is entered in host byte order and converts packet
    to net byte order right _before_ processing pfil(9) hooks.
  - ip_fragment() accepts and emits packet in net byte order.
  - ip_forward(), ip_mloopback() use host byte order (untouched actually).
  - ip_fastforward() no longer modifies packet at all (except ip_ttl).
  - Swapping of byte order there and back removed from the following modules:
    pf(4), ipfw(4), enc(4), if_bridge(4).
  - Swapping of byte order added to ipfilter(4), based on __FreeBSD_version
  - __FreeBSD_version bumped.
  - pfil(9) manual page updated.

Reviewed by:	ray, luigi, eri, melifaro
Tested by:	glebius (LE), ray (BE)
2012-10-06 10:02:11 +00:00
Gleb Smirnoff
3c73180f55 Plug a reference leak: before doing 'goto again' we need to unref
ia->ia_ifa if there is any.

Submitted by:	Andrey Zonov <andrey zonov.org>
2012-07-18 08:58:30 +00:00
Gleb Smirnoff
bf9840512a When ip_output()/ip6_output() is supplied a struct route *ro argument,
it skips FLOWTABLE lookup. However, the non-NULL ro has dual meaning
here: it may be supplied to provide route, and it may be supplied to
store and return to caller the route that ip_output()/ip6_output()
finds. In the latter case skipping FLOWTABLE lookup is pessimisation.

The difference between struct route filled by FLOWTABLE and filled
by rtalloc() family is that the former doesn't hold a reference on
its rtentry. Reference is hold by flow entry, and it is about to
be released in future. Thus, route filled by FLOWTABLE shouldn't
be passed to RTFREE() macro.

- Introduce new flag for struct route/route_in6, that marks route
  not holding a reference on rtentry.
- Introduce new macro RO_RTFREE() that cleans up a struct route
  depending on its kind.
- All callers to ip_output()/ip6_output() that do supply non-NULL
  but empty route should use RO_RTFREE() to free results of
  lookup.
- ip_output()/ip6_output() now do FLOWTABLE lookup always when
  ro->ro_rt == NULL.

Tested by:	tuexen (SCTP part)
2012-07-04 07:37:53 +00:00
Michael Tuexen
3cca425b29 Add a IP_RECVTOS socket option to receive for received UDP/IPv4
packets a cmsg of type IP_RECVTOS which contains the TOS byte.
Much like IP_RECVTTL does for TTL. This allows to implement a
protocol on top of UDP and implementing ECN.

MFC after: 3 days
2012-06-12 14:02:38 +00:00
Mikolaj Golub
fc06cd427e Cache SO_REUSEPORT socket option in inpcb-layer in order to avoid
inp_socket->so_options dereference when we may not acquire the lock on
the inpcb.

This fixes the crash due to NULL pointer dereference in
in_pcbbind_setup() when inp_socket->so_options in a pcb returned by
in_pcblookup_local() was checked.

Reported by:	dave jones <s.dave.jones@gmail.com>, Arnaud Lacombe <lacombar@gmail.com>
Suggested by:	rwatson
Glanced by:	rwatson
Tested by:	dave jones <s.dave.jones@gmail.com>
2011-11-06 10:47:20 +00:00
Bjoern A. Zeeb
05b9d121aa The mbuf_frag_size always was and is file local and not queried from base
user space tools via kvm.  Mark it static.

MFC after:	3 days
2011-04-14 09:47:09 +00:00
Bjoern A. Zeeb
c744cde428 Try to catch a possible divide-by-zero as early as possible if "mtu" is 0
(also test for negative MTUs if checking it anyway).
An MTU of 0 is arguably a bug elsewhere, but this at least gives us some
more debugging hints.

Sponsored by:	ISPsystem (Early 2010)
MFC after:	1 week
2010-12-31 21:47:11 +00:00
Attilio Rao
5f6bf4518d IP_BINDANY is not correctly handled in getsockopt() case.
Fix it by specifying the correct bits.

Sponsored by:	Sandvine Incorporated
Reviewed by:	bz, emaste, rstone
Obtained from:	Sandvine Incorporated
MFC after:	10 days
2010-09-24 14:38:54 +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
Randall Stewart
1966e5b5a1 The proper fix for the delayed SCTP checksum is to
have the delayed function take an argument as to the offset
to the SCTP header. This allows it to work for V4 and V6.
This of course means changing all callers of the function
to either pass the header len, if they have it, or create
it (ip_hl << 2 or sizeof(ip6_hdr)).
PR:		144529
MFC after:	2 weeks
2010-03-12 22:58:52 +00:00
Kip Macy
d4121a02c0 - restructure flowtable to support ipv6
- add a name argument to flowtable_alloc for printing with ddb commands
- extend ddb commands to print destination address or 4-tuples
- don't parse ports in ulp header if FL_HASH_ALL is not passed
- add kern_flowtable_insert to enable more generic use of flowtable
  (e.g. system calls for adding entries)
- don't hash loopback addresses
- cleanup whitespace
- keep statistics per-cpu for per-cpu flowtables to avoid cache line contention
- add sysctls to accumulate stats and report aggregate

MFC after:	7 days
2010-03-12 05:03:26 +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
Bjoern A. Zeeb
fc74d005d9 Make the compiler happy after r201125:
- + remove two unnecessary initializations in ip_output;
+ + remove one unnecessary initializations in ip_output;
2009-12-28 21:14:18 +00:00
Luigi Rizzo
ec396e61ed introduce a local variable rte acting as a cache of ro->ro_rt
within ip_output, achieving (in random order of importance):
- a reduction of the number of 'r's in the source code;
- improved legibility;
- a reduction of 64 bytes in the .text
2009-12-28 14:48:32 +00:00
Luigi Rizzo
ca8b83b0fa + remove an unused #define print_ip;
+ remove two unnecessary initializations in ip_output;
+ localize 'len';
+ introduce a temporary variable n to count the number of fragments,
  the compiler seems unable to identify a common subexpression
  (written 3 times, used twice);
+ document some assumptions on ip_len and ip_hl
2009-12-28 14:09:46 +00:00
Edward Tomasz Napierala
4f7418a09f Remove ifdefed out part of code, which seems to have originated a decade ago
in OpenBSD.  As it is now, there is no way for this to be useful, since IPsec
is free to forward packets via whatever interface it wants, so checking
capabilities of the interface passed from ip_output (fetched from the routing
table) serves no purpose.

Discussed with:	sam@
2009-11-09 19:53:34 +00:00
Julian Elischer
0b4b0b0fee Virtualize the pfil hooks so that different jails may chose different
packet filters. ALso allows ipfw to be enabled on on ejail and disabled
on another. In 8.0 it's a global setting.

Sitting aroung in tree waiting to commit for: 2 months
MFC after:	2 months
2009-10-11 05:59:43 +00:00
Qing Li
0437a93339 Do not try to free the rt_lle entry of the cached route in
ip_output() if the cached route was not initialized from the
flow-table. The rt_lle entry is invalid unless it has been
initialized through the flow-table.

Reviewed by:	kmacy, rwatson
MFC after:	immediately
2009-08-28 05:37:31 +00:00
Kip Macy
3ee42584f9 - change the interface to flowtable_lookup so that we don't rely on
the mbuf for obtaining the fib index
 - check that a cached flow corresponds to the same fib index as the
   packet for which we are doing the lookup
 - at interface detach time flush any flows referencing stale rtentrys
   associated with the interface that is going away (fixes reported
   panics)
 - reduce the time between cleans in case the cleaner is running at
   the time the eventhandler is called and the wakeup is missed less
   time will elapse before the eventhandler returns
 - separate per-vnet initialization from global initialization
   (pointed out by jeli@)

Reviewed by:	sam@
Approved by:	re@
2009-08-18 20:28:58 +00:00
Qing Li
3ef5e21d01 In function ip_output(), the cached route is flushed when there is a
mismatch between the cached entry and the intended destination. The
cached rtentry{} is flushed but the associated llentry{} is not. This
causes the wrong destination MAC address being used in the output
packets. The fix is to flush the llentry{} when rtentry{} is cleared.

Reviewed by:	kmacy, rwatson
Approved by:	re
2009-08-14 23:44:59 +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
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
Robert Watson
8c0fec805f Modify most routines returning 'struct ifaddr *' to return references
rather than pointers, requiring callers to properly dispose of those
references.  The following routines now return references:

  ifaddr_byindex
  ifa_ifwithaddr
  ifa_ifwithbroadaddr
  ifa_ifwithdstaddr
  ifa_ifwithnet
  ifaof_ifpforaddr
  ifa_ifwithroute
  ifa_ifwithroute_fib
  rt_getifa
  rt_getifa_fib
  IFP_TO_IA
  ip_rtaddr
  in6_ifawithifp
  in6ifa_ifpforlinklocal
  in6ifa_ifpwithaddr
  in6_ifadd
  carp_iamatch6
  ip6_getdstifaddr

Remove unused macro which didn't have required referencing:

  IFP_TO_IA6

This closes many small races in which changes to interface
or address lists while an ifaddr was in use could lead to use of freed
memory (etc).  In a few cases, add missing if_addr_list locking
required to safely acquire references.

Because of a lack of deep copying support, we accept a race in which
an in6_ifaddr pointed to by mbuf tags and extracted with
ip6_getdstifaddr() doesn't hold a reference while in transmit.  Once
we have mbuf tag deep copy support, this can be fixed.

Reviewed by:	bz
Obtained from:	Apple, Inc. (portions)
MFC after:	6 weeks (portions)
2009-06-23 20:19:09 +00:00