Commit Graph

112 Commits

Author SHA1 Message Date
Jiri Benc 15e318bdc6 xfrm: simplify xfrm_address_t use
In many places, the a6 field is typecasted to struct in6_addr. As the
fields are in union anyway, just add in6_addr type to the union and
get rid of the typecasting.

Modifying the uapi header is okay, the union has still the same size.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-31 13:58:35 -04:00
Ian Morris 63159f29be ipv6: coding style: comparison for equality with NULL
The ipv6 code uses a mixture of coding styles. In some instances check for NULL
pointer is done as x == NULL and sometimes as !x. !x is preferred according to
checkpatch and this patch makes the code consistent by adopting the latter
form.

No changes detected by objdiff.

Signed-off-by: Ian Morris <ipm@chirality.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-31 13:51:54 -04:00
David S. Miller 0fa74a4be4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/emulex/benet/be_main.c
	net/core/sysctl_net_core.c
	net/ipv4/inet_diag.c

The be_main.c conflict resolution was really tricky.  The conflict
hunks generated by GIT were very unhelpful, to say the least.  It
split functions in half and moved them around, when the real actual
conflict only existed solely inside of one function, that being
be_map_pci_bars().

So instead, to resolve this, I checked out be_main.c from the top
of net-next, then I applied the be_main.c changes from 'net' since
the last time I merged.  And this worked beautifully.

The inet_diag.c and sysctl_net_core.c conflicts were simple
overlapping changes, and were easily to resolve.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-20 18:51:09 -04:00
Eric W. Biederman ddb3b6033c net: Remove protocol from struct dst_ops
After my change to neigh_hh_init to obtain the protocol from the
neigh_table there are no more users of protocol in struct dst_ops.
Remove the protocol field from dst_ops and all of it's initializers.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-09 16:06:10 -04:00
Hajime Tazaki cd3bafc73d xfrm6: Fix a offset value for network header in _decode_session6
When a network-layer header has multiple IPv6 extension headers, then offset
for mobility header goes wrong. This regression breaks an xfrm policy lookup
for a particular receive packet. Binding update packets of Mobile IPv6
are all discarded without this fix.

Fixes: de3b7a06df ("xfrm6: Fix transport header offset in _decode_session6.")
Signed-off-by: Hajime Tazaki <tazaki@sfc.wide.ad.jp>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2015-02-06 07:00:32 +01:00
Steffen Klassert f855691975 xfrm6: Fix the nexthdr offset in _decode_session6.
xfrm_decode_session() was originally designed for the
usage in the receive path where the correct nexthdr offset
is stored in IP6CB(skb)->nhoff. Over time this function
spread to code that is used in the output path (netfilter,
vti) where IP6CB(skb)->nhoff is not set. As a result, we
get a wrong nexthdr and the upper layer flow informations
are wrong. This can leed to incorrect policy lookups.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2014-12-08 07:56:18 +01:00
Steffen Klassert de3b7a06df xfrm6: Fix transport header offset in _decode_session6.
skb->transport_header might not be valid when we do a reverse
decode because the ipv6 tunnel error handlers don't update it
to the inner transport header. This leads to a wrong offset
calculation and to wrong layer 4 informations. We fix this
by using the size of the ipv6 header as the first offset.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2014-12-08 07:38:14 +01:00
Li RongQing 789f202326 xfrm6: fix a potential use after free in xfrm6_policy.c
pskb_may_pull() maybe change skb->data and make nh and exthdr pointer
oboslete, so recompute the nd and exthdr

Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-22 15:38:48 -04:00
Ian Morris 67ba4152e8 ipv6: White-space cleansing : Line Layouts
This patch makes no changes to the logic of the code but simply addresses
coding style issues as detected by checkpatch.

Both objdump and diff -w show no differences.

A number of items are addressed in this patch:
* Multiple spaces converted to tabs
* Spaces before tabs removed.
* Spaces in pointer typing cleansed (char *)foo etc.
* Remove space after sizeof
* Ensure spacing around comparators such as if statements.

Signed-off-by: Ian Morris <ipm@chirality.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-24 22:37:52 -07:00
Steffen Klassert 7e14ea1521 xfrm6: Add IPsec protocol multiplexer
This patch adds an IPsec protocol multiplexer for ipv6. With
this it is possible to add alternative protocol handlers, as
needed for IPsec virtual tunnel interfaces.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2014-03-14 07:28:07 +01:00
Steffen Klassert 84502b5ef9 xfrm: Fix null pointer dereference when decoding sessions
On some codepaths the skb does not have a dst entry
when xfrm_decode_session() is called. So check for
a valid skb_dst() before dereferencing the device
interface index. We use 0 as the device index if
there is no valid skb_dst(), or at reverse decoding
we use skb_iif as device interface index.

Bug was introduced with git commit bafd4bd4dc
("xfrm: Decode sessions with output interface.").

Reported-by: Meelis Roos <mroos@linux.ee>
Tested-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2013-11-01 07:08:46 +01:00
Steffen Klassert eeb1b73378 xfrm: Increase the garbage collector threshold
With the removal of the routing cache, we lost the
option to tweak the garbage collector threshold
along with the maximum routing cache size. So git
commit 703fb94ec ("xfrm: Fix the gc threshold value
for ipv4") moved back to a static threshold.

It turned out that the current threshold before we
start garbage collecting is much to small for some
workloads, so increase it from 1024 to 32768. This
means that we start the garbage collector if we have
more than 32768 dst entries in the system and refuse
new allocations if we are above 65536.

Reported-by: Wolfgang Walter <linux@stwm.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2013-10-28 07:37:52 +01:00
Steffen Klassert bafd4bd4dc xfrm: Decode sessions with output interface.
The output interface matching does not work on forward
policy lookups, the output interface of the flowi is
always 0. Fix this by setting the output interface when
we decode the session.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2013-09-16 09:39:43 +02:00
Cong Wang 84c4a9dfbf xfrm6: release dev before returning error
We forget to call dev_put() on error path in xfrm6_fill_dst(),
its caller doesn't handle this.

Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-11 17:40:15 -07:00
Michal Kubecek 8d068875ca xfrm: make gc_thresh configurable in all namespaces
The xfrm gc threshold can be configured via xfrm{4,6}_gc_thresh
sysctl but currently only in init_net, other namespaces always
use the default value. This can substantially limit the number
of IPsec tunnels that can be effectively used.

Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2013-02-06 11:36:29 +01:00
YOSHIFUJI Hideaki / 吉藤英明 887c95cc1d ipv6: Complete neighbour entry removal from dst_entry.
CC: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-17 18:38:19 -05:00
Steffen Klassert 0afe21fdf6 xfrm6: Remove commented out function call to xfrm6_input_fini
xfrm6_input_fini() is not in the tree since more than 10 years,
so remove the commented out function call.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2012-11-16 08:07:56 +01:00
Steffen Klassert c381328659 xfrm: Use a static gc threshold value for ipv6
Unlike ipv4 did, ipv6 does not handle the maximum number of cached
routes dynamically. So no need to try to handle the IPsec gc threshold
value dynamically. This patch sets the IPsec gc threshold value back to
1024 routes, as it is for non-IPsec routes.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2012-11-15 09:00:18 +01:00
Amerigo Wang 07a936260a ipv6: use IS_ENABLED()
#if defined(CONFIG_FOO) || defined(CONFIG_FOO_MODULE)

can be replaced by

#if IS_ENABLED(CONFIG_FOO)

Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-01 12:41:35 -04:00
Patrick McHardy 9d7b0fc1ef net: ipv6: fix oops in inet_putpeer()
Commit 97bab73f (inet: Hide route peer accesses behind helpers.) introduced
a bug in xfrm6_policy_destroy(). The xfrm_dst's _rt6i_peer member is not
initialized, causing a false positive result from inetpeer_ptr_is_peer(),
which in turn causes a NULL pointer dereference in inet_putpeer().

Pid: 314, comm: kworker/0:1 Not tainted 3.6.0-rc1+ #17 To Be Filled By O.E.M. To Be Filled By O.E.M./P4S800D-X
EIP: 0060:[<c03abf93>] EFLAGS: 00010246 CPU: 0
EIP is at inet_putpeer+0xe/0x16
EAX: 00000000 EBX: f3481700 ECX: 00000000 EDX: 000dd641
ESI: f3481700 EDI: c05e949c EBP: f551def4 ESP: f551def4
 DS: 007b ES: 007b FS: 0000 GS: 00e0 SS: 0068
CR0: 8005003b CR2: 00000070 CR3: 3243d000 CR4: 00000750
DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
DR6: ffff0ff0 DR7: 00000400
 f551df04 c0423de1 00000000 f3481700 f551df18 c038d5f7 f254b9f8 f551df28
 f34f85d8 f551df20 c03ef48d f551df3c c0396870 f30697e8 f24e1738 c05e98f4
 f5509540 c05cd2b4 f551df7c c0142d2b c043feb5 f5509540 00000000 c05cd2e8
 [<c0423de1>] xfrm6_dst_destroy+0x42/0xdb
 [<c038d5f7>] dst_destroy+0x1d/0xa4
 [<c03ef48d>] xfrm_bundle_flo_delete+0x2b/0x36
 [<c0396870>] flow_cache_gc_task+0x85/0x9f
 [<c0142d2b>] process_one_work+0x122/0x441
 [<c043feb5>] ? apic_timer_interrupt+0x31/0x38
 [<c03967eb>] ? flow_cache_new_hashrnd+0x2b/0x2b
 [<c0143e2d>] worker_thread+0x113/0x3cc

Fix by adding a init_dst() callback to struct xfrm_policy_afinfo to
properly initialize the dst's peer pointer.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-20 02:56:56 -07:00
David S. Miller 6700c2709c net: Pass optional SKB and SK arguments to dst_ops->{update_pmtu,redirect}()
This will be used so that we can compose a full flow key.

Even though we have a route in this context, we need more.  In the
future the routes will be without destination address, source address,
etc. keying.  One ipv4 route will cover entire subnets, etc.

In this environment we have to have a way to possess persistent storage
for redirects and PMTU information.  This persistent storage will exist
in the FIB tables, and that's why we'll need to be able to rebuild a
full lookup flow key here.  Using that flow key will do a fib_lookup()
and create/update the persistent entry.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-17 03:29:28 -07:00
David S. Miller ec18d9a269 ipv6: Add redirect support to all protocol icmp error handlers.
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-12 00:25:15 -07:00
David S. Miller 97cac0821a ipv6: Store route neighbour in rt6_info struct.
This makes for a simplified conversion away from dst_get_neighbour*().

All code outside of ipv6 will use neigh lookups via dst_neigh_lookup*().

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-05 02:41:58 -07:00
David S. Miller 97bab73f98 inet: Hide route peer accesses behind helpers.
We encode the pointer(s) into an unsigned long with one state bit.

The state bit is used so we can store the inetpeer tree root to use
when resolving the peer later.

Later the peer roots will be per-FIB table, and this change works to
facilitate that.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-11 02:08:47 -07:00
Eric W. Biederman ec8f23ce0f net: Convert all sysctl registrations to register_net_sysctl
This results in code with less boiler plate that is a bit easier
to read.

Additionally stops us from using compatibility code in the sysctl
core, hastening the day when the compatibility code can be removed.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-20 21:22:30 -04:00
Alexey Dobriyan 4e3fd7a06d net: remove ipv6_addr_copy()
C assignment can handle struct in6_addr copying.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-22 16:43:32 -05:00
Eric Dumazet b71d1d426d inet: constify ip headers and in6_addr
Add const qualifiers to structs iphdr, ipv6hdr and in6_addr pointers
where possible, to make code intention more obvious.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-22 11:04:14 -07:00
David S. Miller 1958b856c1 net: Put fl6_* macros to struct flowi6 and use them again.
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-12 15:08:55 -08:00
David S. Miller 4c9483b2fb ipv6: Convert to use flowi6 where applicable.
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-12 15:08:54 -08:00
David S. Miller 7e1dc7b6f7 net: Use flowi4 and flowi6 in xfrm layer.
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-12 15:08:52 -08:00
David S. Miller 6281dcc94a net: Make flowi ports AF dependent.
Create two sets of port member accessors, one set prefixed by fl4_*
and the other prefixed by fl6_*

This will let us to create AF optimal flow instances.

It will work because every context in which we access the ports,
we have to be fully aware of which AF the flowi is anyways.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-12 15:08:46 -08:00
David S. Miller 1d28f42c1b net: Put flowi_* prefix on AF independent members of struct flowi
I intend to turn struct flowi into a union of AF specific flowi
structs.  There will be a common structure that each variant includes
first, much like struct sock_common.

This is the first step to move in that direction.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-12 15:08:44 -08:00
David S. Miller 2774c131b1 xfrm: Handle blackhole route creation via afinfo.
That way we don't have to potentially do this in every xfrm_lookup()
caller.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-01 14:59:04 -08:00
David S. Miller 5e6b930f21 xfrm: Const'ify address arguments to ->dst_lookup()
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-02-23 23:07:38 -08:00
David S. Miller 0c7b3eefb4 xfrm: Mark flowi arg to ->fill_dst() const.
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-02-22 17:48:57 -08:00
David S. Miller 05d8402576 xfrm: Mark flowi arg to ->get_tos() const.
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-02-22 17:47:10 -08:00
David S. Miller 62fa8a846d net: Implement read-only protection and COW'ing of metrics.
Routing metrics are now copy-on-write.

Initially a route entry points it's metrics at a read-only location.
If a routing table entry exists, it will point there.  Else it will
point at the all zero metric place-holder called 'dst_default_metrics'.

The writeability state of the metrics is stored in the low bits of the
metrics pointer, we have two bits left to spare if we want to store
more states.

For the initial implementation, COW is implemented simply via kmalloc.
However future enhancements will change this to place the writable
metrics somewhere else, in order to increase sharing.  Very likely
this "somewhere else" will be the inetpeer cache.

Note also that this means that metrics updates may transiently fail
if we cannot COW the metrics successfully.

But even by itself, this patch should decrease memory usage and
increase cache locality especially for routing workloads.  In those
cases the read-only metric copies stay in place and never get written
to.

TCP workloads where metrics get updated, and those rare cases where
PMTU triggers occur, will take a very slight performance hit.  But
that hit will be alleviated when the long-term writable metrics
move to a more sharable location.

Since the metrics storage went from a u32 array of RTAX_MAX entries to
what is essentially a pointer, some retooling of the dst_entry layout
was necessary.

Most importantly, we need to preserve the alignment of the reference
count so that it doesn't share cache lines with the read-mostly state,
as per Eric Dumazet's alignment assertion checks.

The only non-trivial bit here is the move of the 'flags' member into
the writeable cacheline.  This is OK since we are always accessing the
flags around the same moment when we made a modification to the
reference count.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-26 20:51:05 -08:00
David S. Miller 7cc2edb834 xfrm6: Don't forget to propagate peer into ipsec route.
Like ipv4, we have to propagate the ipv6 route peer into
the ipsec top-level route during instantiation.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-26 13:41:03 -08:00
Eric Dumazet fc66f95c68 net dst: use a percpu_counter to track entries
struct dst_ops tracks number of allocated dst in an atomic_t field,
subject to high cache line contention in stress workload.

Switch to a percpu_counter, to reduce number of time we need to dirty a
central location. Place it on a separate cache line to avoid dirtying
read only fields.

Stress test :

(Sending 160.000.000 UDP frames,
IP route cache disabled, dual E5540 @2.53GHz,
32bit kernel, FIB_TRIE, SLUB/NUMA)

Before:

real    0m51.179s
user    0m15.329s
sys     10m15.942s

After:

real	0m45.570s
user	0m15.525s
sys	9m56.669s

With a small reordering of struct neighbour fields, subject of a
following patch, (to separate refcnt from other read mostly fields)

real	0m41.841s
user	0m15.261s
sys	8m45.949s

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-10-11 13:06:53 -07:00
Eric Dumazet a02cec2155 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>
2010-09-23 14:33:39 -07:00
Peter Kosyh 44b451f163 xfrm: fix xfrm by MARK logic
While using xfrm by MARK feature in
2.6.34 - 2.6.35 kernels, the mark
is always cleared in flowi structure via memset in
_decode_session4 (net/ipv4/xfrm4_policy.c), so
the policy lookup fails.
IPv6 code is affected by this bug too.

Signed-off-by: Peter Kosyh <p.kosyh@gmail.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-07-04 11:46:07 -07:00
David S. Miller e1703b36c3 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	drivers/net/e100.c
	drivers/net/e1000e/netdev.c
2010-04-27 12:49:13 -07:00
Nicolas Dichtel bc8e4b954e xfrm6: ensure to use the same dev when building a bundle
When building a bundle, we set dst.dev and rt6.rt6i_idev.
We must ensure to set the same device for both fields.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-21 16:25:30 -07:00
Timo Teräs 80c802f307 xfrm: cache bundles instead of policies for outgoing flows
__xfrm_lookup() is called for each packet transmitted out of
system. The xfrm_find_bundle() does a linear search which can
kill system performance depending on how many bundles are
required per policy.

This modifies __xfrm_lookup() to store bundles directly in
the flow cache. If we did not get a hit, we just create a new
bundle instead of doing slow search. This means that we can now
get multiple xfrm_dst's for same flow (on per-cpu basis).

Signed-off-by: Timo Teras <timo.teras@iki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-07 03:43:19 -07:00
Herbert Xu 87c1e12b5e ipsec: Fix bogus bundle flowi
When I merged the bundle creation code, I introduced a bogus
flowi value in the bundle.  Instead of getting from the caller,
it was instead set to the flow in the route object, which is
totally different.

The end result is that the bundles we created never match, and
we instead end up with an ever growing bundle list.

Thanks to Jamal for find this problem.

Reported-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Acked-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-03 01:04:37 -08:00
Alexey Dobriyan d7c7544c3d netns xfrm: deal with dst entries in netns
GC is non-existent in netns, so after you hit GC threshold, no new
dst entries will be created until someone triggers cleanup in init_net.

Make xfrm4_dst_ops and xfrm6_dst_ops per-netns.
This is not done in a generic way, because it woule waste
(AF_MAX - 2) * sizeof(struct dst_ops) bytes per-netns.

Reorder GC threshold initialization so it'd be done before registering
XFRM policies.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-24 22:47:53 -08:00
Eric W. Biederman f8572d8f2a sysctl net: Remove unused binary sysctl code
Now that sys_sysctl is a compatiblity wrapper around /proc/sys
all sysctl strategy routines, and all ctl_name and strategy
entries in the sysctl tables are unused, and can be
revmoed.

In addition neigh_sysctl_register has been modified to no longer
take a strategy argument and it's callers have been modified not
to pass one.

Cc: "David Miller" <davem@davemloft.net>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: netdev@vger.kernel.org
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2009-11-12 02:05:06 -08:00
David S. Miller db71789c01 xfrm6: Fix xfrm6_policy.c build when SYSCTL disabled.
Same as how Randy Dunlap fixed the ipv4 side of things.

Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-04 20:32:16 -07:00
Neil Horman a33bc5c151 xfrm: select sane defaults for xfrm[4|6] gc_thresh
Choose saner defaults for xfrm[4|6] gc_thresh values on init

Currently, the xfrm[4|6] code has hard-coded initial gc_thresh values
(set to 1024).  Given that the ipv4 and ipv6 routing caches are sized
dynamically at boot time, the static selections can be non-sensical.
This patch dynamically selects an appropriate gc threshold based on
the corresponding main routing table size, using the assumption that
we should in the worst case be able to handle as many connections as
the routing table can.

For ipv4, the maximum route cache size is 16 * the number of hash
buckets in the route cache.  Given that xfrm4 starts garbage
collection at the gc_thresh and prevents new allocations at 2 *
gc_thresh, we set gc_thresh to half the maximum route cache size.

For ipv6, its a bit trickier.  there is no maximum route cache size,
but the ipv6 dst_ops gc_thresh is statically set to 1024.  It seems
sane to select a simmilar gc_thresh for the xfrm6 code that is half
the number of hash buckets in the v6 route cache times 16 (like the v4
code does).

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-07-30 18:52:15 -07:00
Neil Horman a44a4a006b xfrm: export xfrm garbage collector thresholds via sysctl
Export garbage collector thresholds for xfrm[4|6]_dst_ops

Had a problem reported to me recently in which a high volume of ipsec
connections on a system began reporting ENOBUFS for new connections
eventually.

It seemed that after about 2000 connections we started being unable to
create more.  A quick look revealed that the xfrm code used a dst_ops
structure that limited the gc_thresh value to 1024, and always
dropped route cache entries after 2x the gc_thresh.

It seems the most direct solution is to export the gc_thresh values in
the xfrm[4|6] dst_ops as sysctls, like the main routing table does, so
that higher volumes of connections can be supported.  This patch has
been tested and allows the reporter to increase their ipsec connection
volume successfully.

Reported-by: Joe Nall <joe@nall.com>
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>

ipv4/xfrm4_policy.c |   18 ++++++++++++++++++
ipv6/xfrm6_policy.c |   18 ++++++++++++++++++
2 files changed, 36 insertions(+)
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-07-27 11:35:32 -07:00