Commit Graph

95 Commits

Author SHA1 Message Date
YOSHIFUJI Hideaki
878628fbf2 [NET] NETNS: Omit namespace comparision without CONFIG_NET_NS.
Introduce an inline net_eq() to compare two namespaces.
Without CONFIG_NET_NS, since no namespace other than &init_net
exists, it is always 1.

We do not need to convert 1) inline vs inline and
2) inline vs &init_net comparisons.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
2008-03-26 04:40:00 +09:00
YOSHIFUJI Hideaki
3b1e0a655f [NET] NETNS: Omit sock->sk_net without CONFIG_NET_NS.
Introduce per-sock inlines: sock_net(), sock_net_set()
and per-inet_timewait_sock inlines: twsk_net(), twsk_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 04:39:55 +09:00
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
Denis V. Lunev
05cf89d40c [NETNS]: Process INET socket layer in the correct namespace.
Replace all the reast of the init_net with a proper net on the socket
layer.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-24 15:31:35 -07:00
Denis V. Lunev
7a6adb92fe [NETNS]: Add namespace parameter to ip_cmsg_send.
Pass the init_net there for now.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-24 15:30:27 -07:00
Pavel Emelyanov
15439febb0 [NETNS][UDP]: Register /proc/net/udp in a namespace.
After the commit a91275eff4 ([NETNS][IPV6]
udp - make proc handle the network namespace) it is now possible to make
this file present in newly created namespaces.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-24 14:53:49 -07:00
Pavel Emelyanov
6ba5a3c52d [UDP]: Make full use of proto.h.udp_hash innovation.
After this we have only udp_lib_get_port to get the port and two 
stubs for ipv4 and ipv6. No difference in udp and udplite except
for initialized h.udp_hash member.

I tried to find a graceful way to drop the only difference between
udp_v4_get_port and udp_v6_get_port (i.e. the rcv_saddr comparison 
routine), but adding one more callback on the struct proto didn't 
appear such :( Maybe later.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-22 16:51:21 -07:00
Pavel Emelyanov
28518fc170 [NET]: NULL pointer dereference and other nasty things in /proc/net/(tcp|udp)[6]
Commits f40c81 ([NETNS][IPV4] tcp - make proc handle the network
namespaces) and a91275 ([NETNS][IPV6] udp - make proc handle the
network namespace) both introduced bad checks on sockets and tw
buckets to belong to proper net namespace.

I.e. when checking for socket to belong to given net and family the

	do {
		sk = sk_next(sk);
	} while (sk && sk->sk_net != net && sk->sk_family != family);

constructions were used. This is wrong, since as soon as the
sk->sk_net fits the net the socket is immediately returned, even if it
belongs to other family.

As the result four /proc/net/(udp|tcp)[6] entries show wrong info.
The udp6 entry even oopses when dereferencing inet6_sk(sk) pointer:

static void udp6_sock_seq_show(struct seq_file *seq, struct sock *sp, int bucket)
{
	...
        struct ipv6_pinfo *np = inet6_sk(sp);
	...

        dest  = &np->daddr; /* will be NULL for AF_INET sockets */
	...
	seq_printf(...
	           dest->s6_addr32[0], dest->s6_addr32[1],
                   dest->s6_addr32[2], dest->s6_addr32[3],
	...

Fix it by converting && to ||.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-21 15:52:00 -07:00
Daniel Lezcano
0c96d8c50b [NETNS][IPV6] udp6 - make proc per namespace
The proc init/exit functions take a new network namespace parameter in
order to register/unregister /proc/net/udp6 for a namespace.

Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-21 04:14:17 -07:00
Daniel Lezcano
a91275eff4 [NETNS][IPV6] udp - make proc handle the network namespace
This patch makes the common udp proc functions to take care of which
socket they should show taking into account the namespace it belongs.

Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-21 04:11:58 -07:00
David S. Miller
db8dac20d5 [UDP]: Revert udplite and code split.
This reverts commit db1ed684f6 ("[IPV6]
UDP: Rename IPv6 UDP files."), commit
8be8af8fa4 ("[IPV4] UDP: Move
IPv4-specific bits to other file.") and commit
e898d4db27 ("[UDP]: Allow users to
configure UDP-Lite.").

First, udplite is of such small cost, and it is a core protocol just
like TCP and normal UDP are.

We spent enormous amounts of effort to make udplite share as much code
with core UDP as possible.  All of that work is less valuable if we're
just going to slap a config option on udplite support.

It is also causing build failures, as reported on linux-next, showing
that the changeset was not tested very well.  In fact, this is the
second build failure resulting from the udplite change.

Finally, the config options provided was a bool, instead of a modular
option.  Meaning the udplite code does not even get build tested
by allmodconfig builds, and furthermore the user is not presented
with a reasonable modular build option which is particularly needed
by distribution vendors.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-06 16:22:02 -08:00
YOSHIFUJI Hideaki
8be8af8fa4 [IPV4] UDP: Move IPv4-specific bits to other file.
Move IPv4-specific UDP bits from net/ipv4/udp.c into (new) net/ipv4/udp_ipv4.c.
Rename net/ipv4/udplite.c to net/ipv4/udplite_ipv4.c.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
2008-03-04 15:18:22 +09:00
YOSHIFUJI Hideaki
e898d4db27 [UDP]: Allow users to configure UDP-Lite.
Let's give users an option for disabling UDP-Lite (~4K).

old:
|    text	   data	    bss	    dec	    hex	filename
|  286498	  12432	   6072	 305002	  4a76a	net/ipv4/built-in.o
|  193830	   8192	   3204	 205226	  321aa	net/ipv6/ipv6.o

new (without UDP-Lite):
|    text	   data	    bss	    dec	    hex	filename
|  284086	  12136	   5432	 301654	  49a56	net/ipv4/built-in.o
|  191835	   7832	   3076	 202743	  317f7	net/ipv6/ipv6.o

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
2008-03-04 15:18:22 +09:00
Pavel Emelyanov
fa4d3c6210 [NETNS]: Udp sockets per-net lookup.
Add the net parameter to udp_get_port family of calls and
udp_lookup one and use it to filter sockets.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-31 19:28:21 -08:00
Denis V. Lunev
f1b050bf7a [NETNS]: Add namespace parameter to ip_route_output_flow.
Needed to propagate it down to the __ip_route_output_key.

Signed_off_by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 15:11:06 -08:00
YOSHIFUJI Hideaki
fc80be87dc [IPV4] UDP,UDPLITE: Sparse: {__udp4_lib,udp,udplite}_err() are of void.
Fix following sparse warnings:
| net/ipv4/udp.c:421:2: warning: returning void-valued expression
| net/ipv4/udplite.c:38:2: warning: returning void-valued expression

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
2008-01-28 15:10:24 -08:00
Eric Dumazet
65f7651788 [NET]: prot_inuse cleanups and optimizations
1) Cleanups (all functions are prefixed by sock_prot_inuse)

sock_prot_inc_use(prot) -> sock_prot_inuse_add(prot,-1)
sock_prot_dec_use(prot) -> sock_prot_inuse_add(prot,-1)
sock_prot_inuse()       -> sock_prot_inuse_get()

New functions :

sock_prot_inuse_init() and sock_prot_inuse_free() to abstract pcounter use.

2) if CONFIG_PROC_FS=n, we can zap 'inuse' member from "struct proto",
since nobody wants to read the inuse value.

This saves 1372 bytes on i386/SMP and some cpu cycles.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 15:00:36 -08:00
Eric Dumazet
9a429c4983 [NET]: Add some acquires/releases sparse annotations.
Add __acquires() and __releases() annotations to suppress some sparse
warnings.

example of warnings :

net/ipv4/udp.c:1555:14: warning: context imbalance in 'udp_seq_start' - wrong
count at exit
net/ipv4/udp.c:1571:13: warning: context imbalance in 'udp_seq_stop' -
unexpected unlock

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 15:00:31 -08:00
Hideo Aoki
95766fff6b [UDP]: Add memory accounting.
Signed-off-by: Takahiro Yasui <tyasui@redhat.com>
Signed-off-by: Hideo Aoki <haoki@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 15:00:19 -08:00
Joe Perches
f97c1e0c6e [IPV4] net/ipv4: Use ipv4_is_<type>
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:58:15 -08:00
Herbert Xu
9055e051b8 [UDP]: Move udp_stats_in6 into net/ipv4/udp.c
Now that external users may increment the counters directly, we need
to ensure that udp_stats_in6 is always available.  Otherwise we'd
either have to requrie the external users to be built as modules or
ipv6 to be built-in.

This isn't too bad because udp_stats_in6 is just a pair of pointers
plus an EXPORT, e.g., just 40 (16 + 24) bytes on x86-64.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:58:06 -08:00
Herbert Xu
a59322be07 [UDP]: Only increment counter on first peek/recv
The previous move of the the UDP inDatagrams counter caused each
peek of the same packet to be counted separately.  This may be
undesirable.

This patch fixes this by adding a bit to sk_buff to record whether
this packet has already been seen through skb_recv_datagram.  We
then only increment the counter when the packet is seen for the
first time.

The only dodgy part is the fact that skb_recv_datagram doesn't have
a good way of returning this new bit of information.  So I've added
a new function __skb_recv_datagram that does return this and made
skb_recv_datagram a wrapper around it.

The plan is to eventually replace all uses of skb_recv_datagram with
this new function at which time it can be renamed its proper name.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:56:34 -08:00
Herbert Xu
1781f7f580 [UDP]: Restore missing inDatagrams increments
The previous move of the the UDP inDatagrams counter caused the
counting of encapsulated packets, SUNRPC data (as opposed to call)
packets and RXRPC packets to go missing.

This patch restores all of these.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:56:33 -08:00
Herbert Xu
27ab256864 [UDP]: Avoid repeated counting of checksum errors due to peeking
Currently it is possible for two processes to peek on the same socket
and end up incrementing the error counter twice for the same packet.

This patch fixes it by making skb_kill_datagram return whether it
succeeded in unlinking the packet and only incrementing the counter
if it did.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:56:32 -08:00
Wang Chen
bbca17680f [UDP]: Counter increment should be in USER mode for recvmsg
System calls should be USER. So change the BH to USER for
UDP*_INC_STATS_BH().

Signed-off-by: Wang Chen <wangchen@cn.fujitsu.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:55:49 -08:00
Wang Chen
b2bf1e2659 [UDP]: Clean up for IS_UDPLITE macro
Since we have macro IS_UDPLITE, we can use it.

Signed-off-by: Wang Chen <wangchen@cn.fujitsu.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:55:48 -08:00
Wang Chen
cb75994ec3 [UDP]: Defer InDataGrams increment until recvmsg() does checksum
Thanks dave, herbert, gerrit, andi and other people for your
discussion about this problem.

UdpInDatagrams can be confusing because it counts packets that
might be dropped later.
Move UdpInDatagrams into recvmsg() as allowed by the RFC.

Signed-off-by: Wang Chen <wangchen@cn.fujitsu.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:55:47 -08:00
Eric Dumazet
47a31a6ffc [IPV4]: Use the {DEFINE|REF}_PROTO_INUSE infrastructure
Trivial patch to make "tcp,udp,udplite,raw" protocols uses the fast
"inuse sockets" infrastructure

Each protocol use then a static percpu var, instead of a dynamic one.
This saves some ram and some cpu cycles

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-11-07 04:08:58 -08:00
Vlad Yasevich
fee9dee730 [UDP]: Make use of inet_iif() when doing socket lookups.
UDP currently uses skb->dev->ifindex which may provide the wrong
information when the socket bound to a specific interface.
This patch makes inet_iif() accessible to UDP and makes UDP use it.

The scenario we are trying to fix is when a client is running on
the same system and the server and both client and server bind to
a non-loopback device.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Acked-by: David L Stevens <dlstevens@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-25 18:54:46 -07:00
Anton Arapov
a25de534f8 [INET]: Justification for local port range robustness.
There is a justifying patch for Stephen's patches. Stephen's patches
disallows using a port range of one single port and brakes the meaning
of the 'remaining' variable, in some places it has different meaning.
My patch gives back the sense of 'remaining' variable. It should mean
how many ports are remaining and nothing else. Also my patch allows
using a single port.

  I sure we must be able to use mentioned port range, this does not
restricted by documentation and does not brake current behavior.

usefull links:
Patches posted by Stephen Hemminger
  http://marc.info/?l=linux-netdev&m=119206106218187&w=2
  http://marc.info/?l=linux-netdev&m=119206109918235&w=2

Andrew Morton's comment
  http://marc.info/?l=linux-kernel&m=119248225007737&w=2

1. Allows using a port range of one single port.
2. Gives back sense of 'remaining' variable.

Signed-off-by: Anton Arapov <aarapov@redhat.com>
Acked-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-18 22:00:17 -07:00
Stephen Hemminger
227b60f510 [INET]: local port range robustness
Expansion of original idea from Denis V. Lunev <den@openvz.org>

Add robustness and locking to the local_port_range sysctl.
1. Enforce that low < high when setting.
2. Use seqlock to ensure atomic update.

The locking might seem like overkill, but there are
cases where sysadmin might want to change value in the
middle of a DoS attack.

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 17:30:46 -07:00
Eric W. Biederman
457c4cbc5a [NET]: Make /proc/net per network namespace
This patch makes /proc/net per network namespace.  It modifies the global
variables proc_net and proc_net_stat to be per network namespace.
The proc_net file helpers are modified to take a network namespace argument,
and all of their callers are fixed to pass &init_net for that argument.
This ensures that all of the /proc/net files are only visible and
usable in the initial network namespace until the code behind them
has been updated to be handle multiple network namespaces.

Making /proc/net per namespace is necessary as at least some files
in /proc/net depend upon the set of network devices which is per
network namespace, and even more files in /proc/net have contents
that are relevant to a single network namespace.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:49:06 -07:00
Stephen Hemminger
32c1da7081 [UDP]: Randomize port selection.
This patch causes UDP port allocation to be randomized like TCP.
The earlier code would always choose same port (ie first empty list).

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:48:31 -07:00
YOSHIFUJI Hideaki
2a0c6c980d [IPV4]: Just increment OutDatagrams once per a datagram.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-14 17:15:19 -07:00
Patrick McHardy
3be550f34b [UDP]: Fix length check.
Rémi Denis-Courmont wrote:
> Right. By the way, shouldn't "len" rather be signed in there?
> 
> 		unsigned int len;
> 
> 		/* if we're overly short, let UDP handle it */
> 		len = skb->len - sizeof(struct udphdr);
> 		if (len <= 0)
> 			goto udp;

It should, but the < 0 case can't happen since __udp4_lib_rcv
already makes sure that we have at least a complete UDP header.

Anyways, this patch fixes it.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 23:06:43 -07:00
James Chapman
067b207b28 [UDP]: Cleanup UDP encapsulation code
This cleanup fell out after adding L2TP support where a new encap_rcv
funcptr was added to struct udp_sock. Have XFRM use the new encap_rcv
funcptr, which allows us to move the XFRM encap code from udp.c into
xfrm4_input.c.

Make xfrm4_rcv_encap() static since it is no longer called externally.

Signed-off-by: James Chapman <jchapman@katalix.com>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:16:53 -07:00
James Chapman
342f0234c7 [UDP]: Introduce UDP encapsulation type for L2TP
This patch adds a new UDP_ENCAP_L2TPINUDP encapsulation type for UDP
sockets. When a UDP socket's encap_type is UDP_ENCAP_L2TPINUDP, the
skb is delivered to a function pointed to by the udp_sock's
encap_rcv funcptr. If the skb isn't wanted by L2TP, it returns >0, which
causes it to be passed through to UDP.

Include padding to put the new encap_rcv field on a 4-byte boundary.

Previously, the only user of UDP encap sockets was ESP, so when
CONFIG_XFRM was not defined, some of the encap code was compiled
out. This patch changes that. As a result, udp_encap_rcv() will
now do a little more work when CONFIG_XFRM is not defined.

Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:15:57 -07:00
David S. Miller
df2bc459a3 [UDP]: Revert 2-pass hashing changes.
This reverts changesets:

6aaf47fa48
b7b5f487ab
de34ed91c4
fc038410b4

There are still some correctness issues recently
discovered which do not have a known fix that doesn't
involve doing a full hash table scan on port bind.

So revert for now.

Signed-off-by: David S. Miller <davem@davemloft.net>
2007-06-07 13:40:50 -07:00
Wei Dong
584bdf8cbd [IPV4]: Fix "ipOutNoRoutes" counter error for TCP and UDP
Signed-off-by: Wei Dong <weidong@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-06-03 18:08:50 -07:00
David S. Miller
fc038410b4 [UDP]: Fix AF-specific references in AF-agnostic code.
__udp_lib_port_inuse() cannot make direct references to
inet_sk(sk)->rcv_saddr as that is ipv4 specific state and
this code is used by ipv6 too.

Use an operations vector to solve this, and this also paves
the way for ipv6 support for non-wild saddr hashing in UDP.

Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-10 23:47:22 -07:00
Michael Opdenacker
59c51591a0 Fix occurrences of "the the "
Signed-off-by: Michael Opdenacker <michael@free-electrons.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2007-05-09 08:57:56 +02:00
David S. Miller
de34ed91c4 [UDP]: Do not allow specific bind when wildcard bind exists.
When allocating local ports, do not allow a bind to a port
with a specific local address when a bind to that port with
a wildcard local address already exists.

Noticed by Linus.

Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-30 14:51:58 -07:00
David S. Miller
b7b5f487ab [IPV4] UDP: Fix endianness bugs in hashing changes.
I accidently applied an earlier version of Eric Dumazet's patch, from
March 21st.  His version from March 30th didn't have these bugs, so
this just interdiffs to the correct patch.

Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-30 13:35:29 -07:00
Eric Dumazet
6aaf47fa48 [PATCH] INET : IPV4 UDP lookups converted to a 2 pass algo
Some people want to have many UDP sockets, binded to a single port but
many different addresses. We currently hash all those sockets into a
single chain.  Processing of incoming packets is very expensive,
because the whole chain must be examined to find the best match.

I chose in this patch to hash UDP sockets with a hash function that
take into account both their port number and address : This has a
drawback because we need two lookups : one with a given address, one
with a wildcard (null) address.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-30 00:26:00 -07:00
Herbert Xu
604763722c [NET]: Treat CHECKSUM_PARTIAL as CHECKSUM_UNNECESSARY
When a transmitted packet is looped back directly, CHECKSUM_PARTIAL
maps to the semantics of CHECKSUM_UNNECESSARY.  Therefore we should
treat it as such in the stack.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:28:43 -07:00
Herbert Xu
663ead3bb8 [NET]: Use csum_start offset instead of skb_transport_header
The skb transport pointer is currently used to specify the start
of the checksum region for transmit checksum offload.  Unfortunately,
the same pointer is also used during receive side processing.

This creates a problem when we want to retransmit a received
packet with partial checksums since the skb transport pointer
would be overwritten.

This patch solves this problem by creating a new 16-bit csum_start
offset value to replace the skb transport header for the purpose
of checksums.  This offset is calculated from skb->head so that
it does not have to change when skb->data changes.

No extra space is required since csum_offset itself fits within
a 16-bit word so we can use the other 16 bits for csum_start.

For backwards compatibility, just before we push a packet with
partial checksums off into the device driver, we set the skb
transport header to what it would have been under the old scheme.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:28:40 -07:00
Arnaldo Carvalho de Melo
88c7664f13 [SK_BUFF]: Introduce icmp_hdr(), remove skb->h.icmph
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:23 -07:00
Arnaldo Carvalho de Melo
4bedb45203 [SK_BUFF]: Introduce udp_hdr(), remove skb->h.uh
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:22 -07:00
Arnaldo Carvalho de Melo
ea2ae17d64 [SK_BUFF]: Introduce skb_transport_offset()
For the quite common 'skb->h.raw - skb->data' sequence.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:16 -07:00
Arnaldo Carvalho de Melo
badff6d01a [SK_BUFF]: Introduce skb_reset_transport_header(skb)
For the common, open coded 'skb->h.raw = skb->data' operation, so that we can
later turn skb->h.raw into a offset, reducing the size of struct sk_buff in
64bit land while possibly keeping it as a pointer on 32bit.

This one touches just the most simple cases:

skb->h.raw = skb->data;
skb->h.raw = {skb_push|[__]skb_pull}()

The next ones will handle the slightly more "complex" cases.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:15 -07:00