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>
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>
- 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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>