Commit Graph

87 Commits

Author SHA1 Message Date
Eric W. Biederman 675071a2ef veth: Fix the byte counters
Commit 44540960 "veth: move loopback logic to common location" introduced
a bug in the packet counters.  I don't understand why that happened as it
is not explained in the comments and the mut check in dev_forward_skb
retains the assumption that skb->len is the total length of the packet.

I just measured this emperically by setting up a veth pair between two
noop network namespaces setting and attempting a telnet connection between
the two.  I saw three packets in each direction and the byte counters were
exactly 14*3 = 42 bytes high in each direction.  I got the actual
packet lengths with tcpdump.

So remove the extra ETH_HLEN from the veth byte count totals.

Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-21 18:24:53 -07:00
Jiri Pirko 84c49d8c3e veth: remove unneeded ifname code from veth_newlink()
The code is not needed because tb[IFLA_IFNAME] is already
processed in rtnl_newlink(). Remove this redundancy.

Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-24 23:18:18 -08:00
Michał Mirosław 0b7967503d net/veth: Fix packet checksumming
We can't change ip_summed from CHECKSUM_PARTIAL to CHECKSUM_NONE
or CHECKSUM_UNNECESSARY because checksum in packet's headers is
not valid and will cause invalid checksum when frame is forwarded.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-12-16 14:41:35 -08:00
Eric Dumazet 807540baae drivers/net: return operator cleanup
Change "return (EXPR);" to "return EXPR;"

return is not a function, parentheses are not required.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-26 18:34:29 -07:00
Eric Dumazet 6ec82562ff veth: Dont kfree_skb() after dev_forward_skb()
In case of congestion, netif_rx() frees the skb, so we must assume
dev_forward_skb() also consume skb.

Bug introduced by commit 445409602c
(veth: move loopback logic to common location)

We must change dev_forward_skb() to always consume skb, and veth to not
double free it.

Bug report : http://marc.info/?l=linux-netdev&m=127310770900442&w=3

Reported-by: Martín Ferrari <martin.ferrari@gmail.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-06 00:53:53 -07:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Patrick McHardy 3729d50212 rtnetlink: support specifying device flags on device creation
commit e8469ed959c373c2ff9e6f488aa5a14971aebe1f
Author: Patrick McHardy <kaber@trash.net>
Date:   Tue Feb 23 20:41:30 2010 +0100

Support specifying the initial device flags when creating a device though
rtnl_link. Devices allocated by rtnl_create_link() are marked as INITIALIZING
in order to surpress netlink registration notifications. To complete setup,
rtnl_configure_link() must be called, which performs the device flag changes
and invokes the deferred notifiers if everything went well.

Two examples:

# add macvlan to eth0
#
$ ip link add link eth0 up allmulticast on type macvlan

[LINK]11: macvlan0@eth0: <BROADCAST,MULTICAST,ALLMULTI,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN
    link/ether 26:f8:84:02:f9:2a brd ff:ff:ff:ff:ff:ff
[ROUTE]ff00::/8 dev macvlan0  table local  metric 256  mtu 1500 advmss 1440 hoplimit 0
[ROUTE]fe80::/64 dev macvlan0  proto kernel  metric 256  mtu 1500 advmss 1440 hoplimit 0
[LINK]11: macvlan0@eth0: <BROADCAST,MULTICAST,ALLMULTI,UP,LOWER_UP> mtu 1500
    link/ether 26:f8:84:02:f9:2a
[ADDR]11: macvlan0    inet6 fe80::24f8:84ff:fe02:f92a/64 scope link
       valid_lft forever preferred_lft forever
[ROUTE]local fe80::24f8:84ff:fe02:f92a via :: dev lo  table local  proto none  metric 0  mtu 16436 advmss 16376 hoplimit 0
[ROUTE]default via fe80::215:e9ff:fef0:10f8 dev macvlan0  proto kernel  metric 1024  mtu 1500 advmss 1440 hoplimit 0
[NEIGH]fe80::215:e9ff:fef0:10f8 dev macvlan0 lladdr 00:15:e9:f0:10:f8 router STALE
[ROUTE]2001:6f8:974::/64 dev macvlan0  proto kernel  metric 256  expires 0sec mtu 1500 advmss 1440 hoplimit 0
[PREFIX]prefix 2001:6f8:974::/64 dev macvlan0 onlink autoconf valid 14400 preferred 131084
[ADDR]11: macvlan0    inet6 2001:6f8:974:0:24f8:84ff:fe02:f92a/64 scope global dynamic
       valid_lft 86399sec preferred_lft 14399sec

# add VLAN to eth1, eth1 is down
#
$ ip link add link eth1 up type vlan id 1000
RTNETLINK answers: Network is down

<no events>

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-02-27 02:43:40 -08:00
Tejun Heo 47d742752d percpu: add __percpu sparse annotations to net drivers
Add __percpu sparse annotations to net drivers.

These annotations are to make sparse consider percpu variables to be
in a different address space and warn if accessed without going
through percpu accessors.  This patch doesn't affect normal builds.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-02-16 23:05:38 -08:00
Linus Torvalds d0316554d3 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (34 commits)
  m68k: rename global variable vmalloc_end to m68k_vmalloc_end
  percpu: add missing per_cpu_ptr_to_phys() definition for UP
  percpu: Fix kdump failure if booted with percpu_alloc=page
  percpu: make misc percpu symbols unique
  percpu: make percpu symbols in ia64 unique
  percpu: make percpu symbols in powerpc unique
  percpu: make percpu symbols in x86 unique
  percpu: make percpu symbols in xen unique
  percpu: make percpu symbols in cpufreq unique
  percpu: make percpu symbols in oprofile unique
  percpu: make percpu symbols in tracer unique
  percpu: make percpu symbols under kernel/ and mm/ unique
  percpu: remove some sparse warnings
  percpu: make alloc_percpu() handle array types
  vmalloc: fix use of non-existent percpu variable in put_cpu_var()
  this_cpu: Use this_cpu_xx in trace_functions_graph.c
  this_cpu: Use this_cpu_xx for ftrace
  this_cpu: Use this_cpu_xx in nmi handling
  this_cpu: Use this_cpu operations in RCU
  this_cpu: Use this_cpu ops for VM statistics
  ...

Fix up trivial (famous last words) global per-cpu naming conflicts in
	arch/x86/kvm/svm.c
	mm/slab.c
2009-12-14 09:58:24 -08:00
David S. Miller 9b963e5d0e Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	drivers/ieee802154/fakehard.c
	drivers/net/e1000e/ich8lan.c
	drivers/net/e1000e/phy.c
	drivers/net/netxen/netxen_nic_init.c
	drivers/net/wireless/ath/ath9k/main.c
2009-11-29 00:57:15 -08:00
Arnd Bergmann 445409602c veth: move loopback logic to common location
The veth driver contains code to forward an skb
from the start_xmit function of one network
device into the receive path of another device.

Moving that code into a common location lets us
reuse the code for direct forwarding of data
between macvlan ports, and possibly in other
drivers.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-26 15:52:58 -08:00
Eric Dumazet 2b1c8b0f92 veth: Fix veth_get_stats()
veth_get_stats() can be called in parallel on several cpus.

It's better to not reset dev->stats as it could give wrong result on
one cpu. Use temporary variables, then store the final results.

Also, we should loop on every possible cpus, not only online cpus,
or cpu hotplug can suddenly give wrong veth stats.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-19 13:16:22 -08:00
Eric W. Biederman 81adee47df net: Support specifying the network namespace upon device creation.
There is no good reason to not support userspace specifying the
network namespace during device creation, and it makes it easier
to create a network device and pass it to a child network namespace
with a well known name.

We have to be careful to ensure that the target network namespace
for the new device exists through the life of the call.  To keep
that logic clear I have factored out the network namespace grabbing
logic into rtnl_link_get_net.

In addtion we need to continue to pass the source network namespace
to the rtnl_link_ops.newlink method so that we can find the base
device source network namespace.

Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
2009-11-08 00:53:51 -08:00
Eric Dumazet 24540535d3 veth: Fix veth_dellink method
In commit 23289a37e2
(net: add a list_head parameter to dellink() method),
I forgot to actually use this parameter in veth_dellink.

I remember feeling a bit uncomfortable about veth_close(),
because it does :

netif_carrier_off(dev);
netif_carrier_off(priv->peer);

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-30 01:00:27 -07:00
Eric Dumazet 23289a37e2 net: add a list_head parameter to dellink() method
Adding a list_head parameter to rtnl_link_ops->dellink() methods
allow us to queue devices on a list, in order to dismantle
them all at once.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-28 02:22:07 -07:00
Christoph Lameter e7dcaa4755 this_cpu: Eliminate get/put_cpu
There are cases where we can use this_cpu_ptr and as the result
of using this_cpu_ptr() we no longer need to determine the
currently executing cpu.

In those places no get/put_cpu combination is needed anymore.
The local cpu variable can be eliminated.

Preemption still needs to be disabled and enabled since the
modifications of the per cpu variables is not atomic. There may
be multiple per cpu variables modified and those must all
be from the same processor.

Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Tejun Heo <tj@kernel.org>
cc: Eric Biederman <ebiederm@aristanetworks.com>
cc: Stephen Hemminger <shemminger@vyatta.com>
cc: David L Stevens <dlstevens@us.ibm.com>
Signed-off-by: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
2009-10-03 19:48:23 +09:00
Stephen Hemminger 0fc0b732ea netdev: drivers should make ethtool_ops const
No need to put ethtool_ops in data, they should be const.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-02 01:03:33 -07:00
Stephen Hemminger 424efe9caf netdev: convert pseudo drivers to netdev_tx_t
These are all drivers that don't touch real hardware.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-01 01:13:40 -07:00
Ben Greear 27a242e92f veth: Zero timestamp in xmit path.
This patch zero's the timestamp before handing the packet to
the peer interface.  This lets the peer recalculate the rx timestamp
if it cares about timestamps.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-07-23 18:01:02 -07:00
Patrick McHardy 6ed106549d net: use NETDEV_TX_OK instead of 0 in ndo_start_xmit() functions
This patch is the result of an automatic spatch transformation to convert
all ndo_start_xmit() return values of 0 to NETDEV_TX_OK.

Some occurences are missed by the automatic conversion, those will be
handled in a seperate patch.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-07-05 19:16:04 -07:00
David S. Miller 11687a1099 Revert "veth: prevent oops caused by netdev destructor"
This reverts commit ae0e8e8220.

This change had two problems:

1) Since it frees the stats in the drivers' close method, we
   can OOPS in the transmit routine.

2) stats are no longer remembered across ifdown/ifup which
   disagrees with how every other device operates.

Thanks to analysis and test patch from Serge E. Hallyn
and initial OOPS report by Sachin Sant.

Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-25 02:45:42 -07:00
Eric Dumazet 60df914e29 veth: dont release skb->dst in veth_xmit()
No need to release skb->dst, its now done by core network.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-29 15:15:30 -07:00
Stephen Hemminger ae0e8e8220 veth: prevent oops caused by netdev destructor
From: Stephen Hemminger <shemminger@vyatta.com>

The veth driver will oops if sysfs hooks are open while module is removed.

The net device destructor can not point to code in a module; basically
there are only two possible safe values: NULL - no destructor, or
free_netdev - free on last use

Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-27 03:04:58 -07:00
Eric Biederman 38d408152a veth: Allow setting the L3 MTU
The limitation to only 1500 byte mtu's limits the utility of the veth
device for testing routing.  So implement implement a configurable
MTU.

For consistency I drop packets on the receive side when they are
larger than the MTU.  I count those drops.  And I allow
a little padding for vlan headers.

I also test the mtu when a new device is created with netlink
because that path currently bypasses the current mtu setting
code.

Signed-off-by: Eric Biederman <ebiederm@aristanetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-03 23:36:04 -08:00
Eric W. Biederman 2cf48a10aa veth: Fix carrier detect
The current implementation of carrier detect in veth is broken.
It reports the link is down until both sides of the veth pair
are administatively up and then forever after it reports link up.

So fix veth so that it only reports link up when both interfaces
of the pair are administratively up.

Signed-off-by: Eric Biederman <ebiederm@aristanetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-01 20:44:21 -08:00
Daniel Lezcano ee92362317 veth : add the set_mac_address capability
Fix lost set_mac_address capability.

Signed-off-by: Daniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-22 00:04:45 -08:00
Stephen Hemminger 008298231a netdev: add more functions to netdevice ops
This patch moves neigh_setup and hard_start_xmit into the network device ops
structure. For bisection, fix all the previously converted drivers as well.
Bonding driver took the biggest hit on this.

Added a prefetch of the hard_start_xmit in the fast path to try and reduce
any impact this would have.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-20 20:14:53 -08:00
Stephen Hemminger 4456e7bdf7 veth: convert to net_device_ops
Convert to net_device_ops function table.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-19 22:42:39 -08:00
Daniel Lezcano 3717746ef8 veth: remove unused list
The veth network device is stored in a list in the netdev private.
AFAICS, this list is never used so I removed this list from the code.

Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-28 23:02:33 -07:00
Daniel Lezcano bb7bba3d56 veth: Remove useless veth field
The veth private structure contains a netdev pointer refering to its peer.
This field is never used and it is pointless because if we can access,
the veth_priv, that means we already have the netdev which is stored
in veth_priv->dev.

Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-28 23:02:33 -07:00
YOSHIFUJI Hideaki c346dca108 [NET] NETNS: Omit net_device->nd_net without CONFIG_NET_NS.
Introduce per-net_device inlines: dev_net(), dev_net_set().
Without CONFIG_NET_NS, no namespace other than &init_net exists.
Let's explicitly define them to help compiler optimizations.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
2008-03-26 04:39:53 +09:00
Daniel Lezcano c15853f2c1 veth: fix dev refcount race
When deleting the veth driver, veth_close calls netif_carrier_off
for the two extremities of the network device. netif_carrier_off on
the peer device will fire an event and hold a reference on the peer
device. Just after, the peer is unregistered taking the rtnl_lock while
the linkwatch_event is scheduled. If __linkwatch_run_queue does not
occurs before the unregistering, unregister_netdevice will wait for
the dev refcount to reach zero holding the rtnl_lock and linkwatch_event
will wait for the rtnl_lock and hold the dev refcount.

Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-20 00:21:47 -08:00
Patrick McHardy 68365458a4 [NET]: rtnl_link: fix use-after-free
When unregistering the rtnl_link_ops, all existing devices using
the ops are destroyed. With nested devices this may lead to a
use-after-free despite the use of for_each_netdev_safe() in case
the upper device is next in the device list and is destroyed
by the NETDEV_UNREGISTER notifier.

The easy fix is to restart scanning the device list after removing
a device. Alternatively we could add new devices to the front of
the list to avoid having dependant devices follow the device they
depend on. A third option would be to only restart scanning if
dev->iflink of the next device matches dev->ifindex of the current
one. For now this seems like the safest solution.

With this patch, the veth rtnl_link_ops unregistration can use
rtnl_link_unregister() directly since it now also handles destruction
of multiple devices at once.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-20 20:31:45 -08:00
Stephen Hemminger ecef969e5b [VETH]: move veth.h to include/linux
Move veth.h from net/ to linux/ since it is a user api, and add it to
user header processing Kbuild.

[ Use header-y as suggested by Sam Ravnborg.  -DaveM ]

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-12-26 19:36:35 -08:00
Jeff Garzik b9f2c0440d [netdrvr] Stop using legacy hooks ->self_test_count, ->get_stats_count
These have been superceded by the new ->get_sset_count() hook.

Signed-off-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:51:45 -07:00
Eric W. Biederman 881d966b48 [NET]: Make the device list and device lookups per namespace.
This patch makes most of the generic device layer network
namespace safe.  This patch makes dev_base_head a
network namespace variable, and then it picks up
a few associated variables.  The functions:
dev_getbyhwaddr
dev_getfirsthwbytype
dev_get_by_flags
dev_get_by_name
__dev_get_by_name
dev_get_by_index
__dev_get_by_index
dev_ioctl
dev_ethtool
dev_load
wireless_process_ioctl

were modified to take a network namespace argument, and
deal with it.

vlan_ioctl_set and brioctl_set were modified so their
hooks will receive a network namespace argument.

So basically anthing in the core of the network stack that was
affected to by the change of dev_base was modified to handle
multiple network namespaces.  The rest of the network stack was
simply modified to explicitly use &init_net the initial network
namespace.  This can be fixed when those components of the network
stack are modified to handle multiple network namespaces.

For now the ifindex generator is left global.

Fundametally ifindex numbers are per namespace, or else
we will have corner case problems with migration when
we get that far.

At the same time there are assumptions in the network stack
that the ifindex of a network device won't change.  Making
the ifindex number global seems a good compromise until
the network stack can cope with ifindex changes when
you change namespaces, and the like.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:49:10 -07:00
Pavel Emelyanov e314dbdc1c [NET]: Virtual ethernet device driver.
Veth stands for Virtual ETHernet. It is a simple tunnel driver
that works at the link layer and looks like a pair of ethernet
devices interconnected with each other.

Mainly it allows to communicate between network namespaces but
it can be used as is as well.

The newlink callback is organized that way to make it easy to
create the peer device in the separate namespace when we have
them in kernel.

This implementation uses another interface - the RTM_NRELINK
message introduced by Patric.

Bug fixes from Daniel Lezcano.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:47:46 -07:00