Commit Graph

16 Commits

Author SHA1 Message Date
Oliver Pinter 53379e57a7 typo fixes in net/core/net_namespace.c
Signed-off-by: Oliver Pinter <oliver.pntr@gmail.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
2008-02-03 17:56:48 +02:00
Benjamin Thery 3ef1355dcb [NET]: Make netns cleanup to run in a separate queue
This patch adds a separate workqueue for cleaning up a network
namespace. If we use the keventd workqueue to execute cleanup_net(),
there is a problem to unregister devices in IPv6. Indeed the code
that cleans up also schedule work in keventd: as long as cleanup_net()
hasn't return, dst_gc_task() cannot run and as long as dst_gc_task() has
not run, there are still some references pending on the net devices and
cleanup_net() can not unregister and exit the keventd workqueue.

Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Acked-by: Denis V. Lunev <den@openvz.org>
Acked-By: Kirill Korotaev <dev@sw.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:35 -08:00
Denis V. Lunev ff4b950277 [NETNS]: Re-export init_net via EXPORT_SYMBOL.
init_net is used added as a parameter to a lot of old API calls, f.e.
ip_dev_find. These calls were exported as EXPORT_SYMBOL. So, export init_net
as EXPORT_SYMBOL to keep networking API consistent.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-23 03:11:42 -08:00
Denis V. Lunev ed160e839d [NET]: Cleanup pernet operation without CONFIG_NET_NS
If CONFIG_NET_NS is not set, the only namespace is possible.

This patch removes list of pernet_operations and cleanups code a bit.
This list is not needed if there are no namespaces. We should just call
->init method.

Additionally, the ->exit will be called on module unloading only. This
case is safe - the code is not discarded. For the in/kernel code, ->exit
should never be called.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-11-13 03:23:21 -08:00
Johann Felix Soden 45a19b0a72 [NETNS]: Fix compiler error in net_namespace.c
Because net_free is called by copy_net_ns before its declaration, the
compiler gives an error. This patch puts net_free before copy_net_ns
to fix this.

The compiler error:
net/core/net_namespace.c: In function 'copy_net_ns':
net/core/net_namespace.c:97: error: implicit declaration of function 'net_free'
net/core/net_namespace.c: At top level:
net/core/net_namespace.c:104: warning: conflicting types for 'net_free'
net/core/net_namespace.c:104: error: static declaration of 'net_free' follows non-static declaration
net/core/net_namespace.c:97: error: previous implicit declaration of 'net_free' was here

The error was introduced by the '[NET]: Hide the dead code in the
net_namespace.c' patch (6a1a3b9f68).

Signed-off-by: Johann Felix Soden <johfel@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-11-07 04:15:02 -08:00
Pavel Emelyanov d57a9212e0 [NET]: Hide the net_ns kmem cache
This cache is only required to create new namespaces,
but we won't have them in CONFIG_NET_NS=n case.

Hide it under the appropriate ifdef.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-11-01 00:46:50 -07:00
Pavel Emelyanov 1a2ee93d28 [NET]: Mark the setup_net as __net_init
The setup_net is called for the init net namespace
only (int the CONFIG_NET_NS=n of course) from the __init
function, so mark it as __net_init to disappear with the
caller after the boot.

Yet again, in the perfect world this has to be under
#ifdef CONFIG_NET_NS, but it isn't guaranteed that every
subsystem is registered *after* the init_net_ns is set
up. After we are sure, that we don't start registering
them before the init net setup, we'll be able to move
this code under the ifdef.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-11-01 00:45:59 -07:00
Pavel Emelyanov 6a1a3b9f68 [NET]: Hide the dead code in the net_namespace.c
The namespace creation/destruction code is never called
if the CONFIG_NET_NS is n, so it's OK to move it under
appropriate ifdef.

The copy_net_ns() in the "n" case checks for flags and
returns -EINVAL when new net ns is requested. In a perfect
world this stub must be in net_namespace.h, but this
function need to know the CLONE_NEWNET value and thus
requires sched.h. On the other hand this header is to be
injected into almost every .c file in the networking code,
and making all this code depend on the sched.h is a
suicidal attempt.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-11-01 00:44:50 -07:00
Pavel Emelyanov 1dba323b3f [NETNS]: Make the init/exit hooks checks outside the loop
When the new pernet something (subsys, device or operations) is
being registered, the init callback is to be called for each
namespace, that currently exitst in the system. During the
unregister, the same is to be done with the exit callback.

However, not every pernet something has both calls, but the
check for the appropriate pointer to be not NULL is performed
inside the for_each_net() loop.

This is (at least) strange, so tune this.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-11-01 00:42:43 -07:00
Daniel Lezcano 310928d963 [NETNS]: fix net released by rcu callback
When a network namespace reference is held by a network subsystem,
and when this reference is decremented in a rcu update callback, we
must ensure that there is no more outstanding rcu update before
trying to free the network namespace.

In the normal case, the rcu_barrier is called when the network namespace
is exiting in the cleanup_net function.

But when a network namespace creation fails, and the subsystems are
undone (like the cleanup), the rcu_barrier is missing.

This patch adds the missing rcu_barrier.

Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-30 21:16:21 -07:00
Pavel Emelyanov 32f0c4cbe4 [NETNS]: Don't memset() netns to zero manually
The newly created net namespace is set to 0 with memset()
in setup_net(). The setup_net() is also called for the
init_net_ns(), which is zeroed naturally as a global var.

So remove this memset and allocate new nets with the
kmem_cache_zalloc().

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:54:59 -07:00
Eric W. Biederman f4618d39a3 [NETNS]: Simplify the network namespace list locking rules.
Denis V. Lunev <den@sw.ru> noticed that the locking rules
for the network namespace list are over complicated and broken.

In particular the current register_netdev_notifier currently
does not take any lock making the for_each_net iteration racy
with network namespace creation and destruction. Oops.

The fact that we need to use for_each_net in rtnl_unlock() when
the rtnetlink support becomes per network namespace makes designing
the proper locking tricky.  In addition we need to be able to call
rtnl_lock() and rtnl_unlock() when we have the net_mutex held.

After thinking about it and looking at the alternatives carefully
it looks like the simplest and most maintainable solution is
to remove net_list_mutex altogether, and to use the rtnl_mutex instead.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:52:55 -07:00
Eric W. Biederman 9dd776b6d7 [NET]: Add network namespace clone & unshare support.
This patch allows you to create a new network namespace
using sys_clone, or sys_unshare.

As the network namespace is still experimental and under development
clone and unshare support is only made available when CONFIG_NET_NS is
selected at compile time.

As this patch introduces network namespace support into code paths
that exist when the CONFIG_NET is not selected there are a few
additions made to net_namespace.h to allow a few more functions
to be used when the networking stack is not compiled in.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:52:46 -07:00
Pavel Emelyanov 768f3591e2 [NETNS]: Cleanup list walking in setup_net and cleanup_net
I proposed introducing a list_for_each_entry_continue_reverse macro
to be used in setup_net() when unrolling the failed ->init callback.

Here is the macro and some more cleanup in the setup_net() itself
to remove one variable from the stack :) The same thing is for the
cleanup_net() - the existing list_for_each_entry_reverse() is used.

Minor, but the code looks nicer.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:51:35 -07:00
David S. Miller 678aa8e4eb [NET]: #if 0 out net_alloc() for now.
We will undo this once it is actually used.

Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:49:14 -07:00
Eric W. Biederman 5f256becd8 [NET]: Basic network namespace infrastructure.
This is the basic infrastructure needed to support network
namespaces.  This infrastructure is:
- Registration functions to support initializing per network
  namespace data when a network namespaces is created or destroyed.

- struct net.  The network namespace data structure.
  This structure will grow as variables are made per network
  namespace but this is the minimal starting point.

- Functions to grab a reference to the network namespace.
  I provide both get/put functions that keep a network namespace
  from being freed.  And hold/release functions serve as weak references
  and will warn if their count is not zero when the data structure
  is freed.  Useful for dealing with more complicated data structures
  like the ipv4 route cache.

- A list of all of the network namespaces so we can iterate over them.

- A slab for the network namespace data structure allowing leaks
  to be spotted.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:49:03 -07:00