Commit Graph

43 Commits

Author SHA1 Message Date
Eric W. Biederman 3a765edadb netns: Add an explicit rcu_barrier to unregister_pernet_{device|subsys}
This allows namespace exit methods to batch work that comes requires an
rcu barrier using call_rcu without having to treat the
unregister_pernet_operations cases specially.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-12-03 12:22:03 -08:00
Eric W. Biederman 04dc7f6be3 net: Move network device exit batching
Move network device exit batching from a special case in
net_namespace.c to using common mechanisms in dev.c

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-12-03 12:22:02 -08:00
Eric W. Biederman 72ad937abd net: Add support for batching network namespace cleanups
- Add exit_list to struct net to support building lists of network
  namespaces to cleanup.

- Add exit_batch to pernet_operations to allow running operations only
  once during a network namespace exit.  Instead of once per network
  namespace.

- Factor opt ops_exit_list and ops_exit_free so the logic with cleanup
  up a network namespace does not need to be duplicated.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-12-03 12:22:01 -08:00
Eric W. Biederman f875bae065 net: Automatically allocate per namespace data.
To get the full benefit of batched network namespace cleanup netowrk
device deletion needs to be performed by the generic code.  When
using register_pernet_gen_device and freeing the data in exit_net
it is impossible to delay allocation until after exit_net has called
as the device uninit methods are no longer safe.

To correct this, and to simplify working with per network namespace data
I have moved allocation and deletion of per network namespace data into
the network namespace core.  The core now frees the data only after
all of the network namespace exit routines have run.

Now it is only required to set the new fields .id and .size
in the pernet_operations structure if you want network namespace
data to be managed for you automatically.

This makes the current register_pernet_gen_device and
register_pernet_gen_subsys routines unnecessary.  For the moment
I have left them as compatibility wrappers in net_namespace.h
They will be removed once all of the users have been updated.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-12-01 16:15:51 -08:00
Eric W. Biederman 2b035b3997 net: Batch network namespace destruction.
It is fairly common to kill several network namespaces at once.  Either
because they are nested one inside the other or because they are cooperating
in multiple machine networking experiments.  As the network stack control logic
does not parallelize easily batch up multiple network namespaces existing
together.

To get the full benefit of batching the virtual network devices to be
removed must be all removed in one batch.  For that purpose I have added
a loop after the last network device operations have run that batches
up all remaining network devices and deletes them.

An extra benefit is that the reorganization slightly shrinks the size
of the per network namespace data structures replaceing a work_struct
with a list_head.

In a trivial test with 4K namespaces this change reduced the cost of
a destroying 4K namespaces from 7+ minutes (at 12% cpu) to 44 seconds
(at 60% cpu).  The bulk of that 44s was spent in inet_twsk_purge.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-12-01 16:15:51 -08:00
Octavian Purdila 09ad9bc752 net: use net_eq to compare nets
Generated with the following semantic patch

@@
struct net *n1;
struct net *n2;
@@
- n1 == n2
+ net_eq(n1, n2)

@@
struct net *n1;
struct net *n2;
@@
- n1 != n2
+ !net_eq(n1, n2)

applied over {include,net,drivers/net}.

Signed-off-by: Octavian Purdila <opurdila@ixiacom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-25 15:14:13 -08:00
David S. Miller aa11d958d1 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	arch/microblaze/include/asm/socket.h
2009-08-12 17:44:53 -07:00
Eric Dumazet 144586301f net: net_assign_generic() fix
memcpy() should take into account size of pointers,
not only number of pointers to copy.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-02 12:20:36 -07:00
Johannes Berg 30ffee8480 net: move and export get_net_ns_by_pid
The function get_net_ns_by_pid(), to get a network
namespace from a pid_t, will be required in cfg80211
as well. Therefore, let's move it to net_namespace.c
and export it. We can't make it a static inline in
the !NETNS case because it needs to verify that the
given pid even exists (and return -ESRCH).

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-07-12 14:03:28 -07:00
Johannes Berg 11a28d373e net: make namespace iteration possible under RCU
All we need to take care of is using proper RCU list
add/del primitives and inserting a synchronize_rcu()
at one place to make sure the exit notifiers are run
after everybody has stopped iterating the list.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-07-12 14:03:25 -07:00
Stephen Hemminger ca0f31125c netns: simplify net_ns_init
The net_ns_init code can be simplified. No need to save error code
if it is only going to panic if it is set 4 lines later.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-21 15:10:31 -07:00
Stephen Hemminger 1f7a2bb4ef netns: remove leftover debugging message
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-21 15:10:05 -07:00
Alexey Dobriyan 088eb2d905 netns 2/2: extract net_create()
net_create() will be used by C/R to create fresh netns on restart.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-04 11:12:14 -07:00
Alexey Dobriyan 4a84822c60 netns 1/2: don't get/put old netns on CLONE_NEWNET
copy_net_ns() doesn't copy anything, it creates fresh netns, so
get/put of old netns isn't needed.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-04 11:11:38 -07:00
Eric W. Biederman 17edde5209 netns: Remove net_alive
It turns out that net_alive is unnecessary, and the original problem
that led to it being added was simply that the icmp code thought
it was a network device and wound up being unable to handle packets
while there were still packets in the network namespace.

Now that icmp and tcp have been fixed to properly register themselves
this problem is no longer present and we have a stronger guarantee
that packets will not arrive in a network namespace then that provided
by net_alive in netif_receive_skb.  So remove net_alive allowing
packet reception run a little faster.

Additionally document the strong reason why network namespace cleanup
is safe so that if something happens again someone else will have
a chance of figuring it out.

Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-03 01:14:27 -08:00
Clemens Noss ebe47d47b7 netns: build fix for net_alloc_generic
net_alloc_generic was defined in #ifdef CONFIG_NET_NS, but used
unconditionally. Move net_alloc_generic out of #ifdef.

Signed-off-by: Clemens Noss <cnoss@gmx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-23 15:37:35 -08:00
Daniel Lezcano 486a87f1e5 netns: fix double free at netns creation
This patch fix a double free when a network namespace fails.
The previous code does a kfree of the net_generic structure when
one of the init subsystem initialization fails.
The 'setup_net' function does kfree(ng) and returns an error.
The caller, 'copy_net_ns', call net_free on error, and this one
calls kfree(net->gen), making this pointer freed twice.

This patch make the code symetric, the net_alloc does the net_generic
allocation and the net_free frees the net_generic.

Signed-off-by: Daniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-22 00:07:53 -08:00
Jiri Slaby 357f5b0b91 NET: net_namespace, fix lock imbalance
register_pernet_gen_subsys omits mutex_unlock in one fail path.
Fix it.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-20 14:39:31 -08:00
David S. Miller a1744d3bee Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:

	drivers/net/wireless/p54/p54common.c
2008-10-31 00:17:34 -07:00
Alexey Dobriyan 485ac57bc1 netns: add register_pernet_gen_subsys/unregister_pernet_gen_subsys
netns ops which are registered with register_pernet_gen_device() are
shutdown strictly before those which are registered with
register_pernet_subsys(). Sometimes this leads to opposite (read: buggy)
shutdown ordering between two modules.

Add register_pernet_gen_subsys()/unregister_pernet_gen_subsys() for modules
which aren't elite enough for entry in struct net, and which can't use
register_pernet_gen_device(). PPTP conntracking module is such one.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-30 23:55:16 -07:00
Alexey Dobriyan 93adcc80f3 net: don't use INIT_RCU_HEAD
call_rcu() will unconditionally rewrite RCU head anyway.
Applies to 
	struct neigh_parms
	struct neigh_table
	struct net
	struct cipso_v4_doi
	struct in_ifaddr
	struct in_device
	rt->u.dst

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-28 13:25:09 -07:00
Alexey Dobriyan 4ef079ccc1 netns: fix net_generic array leak
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-14 22:54:48 -07:00
Alexey Dobriyan b76a461f11 netns: export netns list
Conntrack code will use it for
a) removing expectations and helpers when corresponding module is removed, and
b) removing conntracks when L3 protocol conntrack module is removed.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-10-08 11:35:06 +02:00
Eric W. Biederman b9f75f45a6 netns: Don't receive new packets in a dead network namespace.
Alexey Dobriyan <adobriyan@gmail.com> writes:
> Subject: ICMP sockets destruction vs ICMP packets oops

> After icmp_sk_exit() nuked ICMP sockets, we get an interrupt.
> icmp_reply() wants ICMP socket.
>
> Steps to reproduce:
>
> 	launch shell in new netns
> 	move real NIC to netns
> 	setup routing
> 	ping -i 0
> 	exit from shell
>
> BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
> IP: [<ffffffff803fce17>] icmp_sk+0x17/0x30
> PGD 17f3cd067 PUD 17f3ce067 PMD 0 
> Oops: 0000 [1] PREEMPT SMP DEBUG_PAGEALLOC
> CPU 0 
> Modules linked in: usblp usbcore
> Pid: 0, comm: swapper Not tainted 2.6.26-rc6-netns-ct #4
> RIP: 0010:[<ffffffff803fce17>]  [<ffffffff803fce17>] icmp_sk+0x17/0x30
> RSP: 0018:ffffffff8057fc30  EFLAGS: 00010286
> RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff81017c7db900
> RDX: 0000000000000034 RSI: ffff81017c7db900 RDI: ffff81017dc41800
> RBP: ffffffff8057fc40 R08: 0000000000000001 R09: 000000000000a815
> R10: 0000000000000000 R11: 0000000000000001 R12: ffffffff8057fd28
> R13: ffffffff8057fd00 R14: ffff81017c7db938 R15: ffff81017dc41800
> FS:  0000000000000000(0000) GS:ffffffff80525000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0018 ES: 0018 CR0: 000000008005003b
> CR2: 0000000000000000 CR3: 000000017fcda000 CR4: 00000000000006e0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
> Process swapper (pid: 0, threadinfo ffffffff8053a000, task ffffffff804fa4a0)
> Stack:  0000000000000000 ffff81017c7db900 ffffffff8057fcf0 ffffffff803fcfe4
>  ffffffff804faa38 0000000000000246 0000000000005a40 0000000000000246
>  000000000001ffff ffff81017dd68dc0 0000000000005a40 0000000055342436
> Call Trace:
>  <IRQ>  [<ffffffff803fcfe4>] icmp_reply+0x44/0x1e0
>  [<ffffffff803d3a0a>] ? ip_route_input+0x23a/0x1360
>  [<ffffffff803fd645>] icmp_echo+0x65/0x70
>  [<ffffffff803fd300>] icmp_rcv+0x180/0x1b0
>  [<ffffffff803d6d84>] ip_local_deliver+0xf4/0x1f0
>  [<ffffffff803d71bb>] ip_rcv+0x33b/0x650
>  [<ffffffff803bb16a>] netif_receive_skb+0x27a/0x340
>  [<ffffffff803be57d>] process_backlog+0x9d/0x100
>  [<ffffffff803bdd4d>] net_rx_action+0x18d/0x250
>  [<ffffffff80237be5>] __do_softirq+0x75/0x100
>  [<ffffffff8020c97c>] call_softirq+0x1c/0x30
>  [<ffffffff8020f085>] do_softirq+0x65/0xa0
>  [<ffffffff80237af7>] irq_exit+0x97/0xa0
>  [<ffffffff8020f198>] do_IRQ+0xa8/0x130
>  [<ffffffff80212ee0>] ? mwait_idle+0x0/0x60
>  [<ffffffff8020bc46>] ret_from_intr+0x0/0xf
>  <EOI>  [<ffffffff80212f2c>] ? mwait_idle+0x4c/0x60
>  [<ffffffff80212f23>] ? mwait_idle+0x43/0x60
>  [<ffffffff8020a217>] ? cpu_idle+0x57/0xa0
>  [<ffffffff8040f380>] ? rest_init+0x70/0x80
> Code: 10 5b 41 5c 41 5d 41 5e c9 c3 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 53
> 48 83 ec 08 48 8b 9f 78 01 00 00 e8 2b c7 f1 ff 89 c0 <48> 8b 04 c3 48 83 c4 08
> 5b c9 c3 66 66 66 66 66 2e 0f 1f 84 00
> RIP  [<ffffffff803fce17>] icmp_sk+0x17/0x30
>  RSP <ffffffff8057fc30>
> CR2: 0000000000000000
> ---[ end trace ea161157b76b33e8 ]---
> Kernel panic - not syncing: Aiee, killing interrupt handler!

Receiving packets while we are cleaning up a network namespace is a
racy proposition. It is possible when the packet arrives that we have
removed some but not all of the state we need to fully process it.  We
have the choice of either playing wack-a-mole with the cleanup routines
or simply dropping packets when we don't have a network namespace to
handle them.

Since the check looks inexpensive in netif_receive_skb let's just
drop the incoming packets.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-20 22:16:51 -07:00
Denis V. Lunev 5d1e4468a7 [NETNS]: Make netns refconting debug like a socket one.
Make release_net/hold_net noop for performance-hungry people. This is a debug
staff and should be used in the debug mode only.

Add check for net != NULL in hold/release calls. This will be required
later on.

[ Added minor simplifications suggested by Brian Haley. -DaveM ]

Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-16 01:58:04 -07:00