We can reduce pressure on dst entry refcount that slowdown UDP transmit
path on SMP machines. This pressure is visible on RTP servers when
delivering content to mediagateways, especially big ones, handling
thousand of streams. Several cpus send UDP frames to the same
destination, hence use the same dst entry.

This patch makes ip_append_data() eventually steal the refcount its
callers had to take on the dst entry.

This doesnt avoid all refcounting, but still gives speedups on SMP,
on UDP/RAW transmit path
Signed-off-by: NEric Dumazet <dada1@cosmosbay.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NJianjun Kong <jianjun@zeuux.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

All the callers already have either the net itself, or the place
where to get it from.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This routine deals with ICMP statistics, but doesn't have a
struct net at hands, so add one.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In commits 33c732c3 ([IPV4]: Add raw
drops counter) and a92aa318 ([IPV6]:
Add raw drops counter), Wang Chen added raw drops counter for
/proc/net/raw & /proc/net/raw6

This patch adds this capability to UDP sockets too (/proc/net/udp &
/proc/net/udp6).

This means that 'RcvbufErrors' errors found in /proc/net/snmp can be also
be examined for each udp socket.

# grep Udp: /proc/net/snmp
Udp: InDatagrams NoPorts InErrors OutDatagrams RcvbufErrors SndbufErrors
Udp: 23971006 75 899420 16390693 146348 0

# cat /proc/net/udp
 sl  local_address rem_address   st tx_queue rx_queue tr tm->when retrnsmt  ---
uid  timeout inode ref pointer drops
 75: 00000000:02CB 00000000:0000 07 00000000:00000000 00:00000000 00000000  ---
  0        0 2358 2 ffff81082a538c80 0
111: 00000000:006F 00000000:0000 07 00000000:00000000 00:00000000 00000000  ---
  0        0 2286 2 ffff81042dd35c80 146348

In this example, only port 111 (0x006F) was flooded by messages that
user program could not read fast enough. 146348 messages were lost.
Signed-off-by: NEric Dumazet <dada1@cosmosbay.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

I just noticed "cat /proc/net/raw" was buggy, missing '\n' separators.

I believe this was introduced by commit 8cd850ef 
([RAW]: Cleanup IPv4 raw_seq_show.)

This trivial patch restores correct behavior, and applies to current 
Linus tree (should also be applied to stable tree as well.)
Signed-off-by: NEric Dumazet <dada1@cosmosbay.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Change struct proto destroy function pointer to return void.  Noticed
by Al Viro.
Signed-off-by: NBrian Haley <brian.haley@hp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch removes CVS keywords that weren't updated for a long time
from comments.
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The program below just leaks the raw kernel socket

int main() {
        int fd = socket(PF_INET, SOCK_RAW, IPPROTO_UDP);
        struct sockaddr_in addr;

        memset(&addr, 0, sizeof(addr));
        inet_aton("127.0.0.1", &addr.sin_addr);
        addr.sin_family = AF_INET;
        addr.sin_port = htons(2048);
        sendto(fd,  "a", 1, MSG_MORE, &addr, sizeof(addr));
        return 0;
}

Corked packet is allocated via sock_wmalloc which holds the owner socket,
so one should uncork it and flush all pending data on close. Do this in the
same way as in UDP.
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Acked-by: NAlexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds needed_headroom/needed_tailroom members to struct
net_device and updates many places that allocate sbks to use them. Not
all of them can be converted though, and I'm sure I missed some (I
mostly grepped for LL_RESERVED_SPACE)
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This counter is about to become per-proto-and-per-net, so we'll need 
two arguments to determine which cell in this "table" to work with.

All the places, but proc already pass proper net to it - proc will be
tuned a bit later.

Some indentation with spaces in proc files is done to keep the file
coding style consistent.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

An uppercut - do not use the pcounter on struct proto.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Acked-by: NEric Dumazet <dada1@cosmosbay.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

Without CONFIG_NET_NS, no namespace other than &init_net exists,
no need to store net in seq_net_private.
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

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: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

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: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

Replace all the reast of the init_net with a proper net on the socket
layer.
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pass the init_net there for now.
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Sorry for the patch sequence confusion :| but I found that the similar
thing can be done for raw sockets easily too late.

Expand the proto.h union with the raw_hashinfo member and use it in
raw_prot and rawv6_prot. This allows to drop the protocol specific
versions of hash and unhash callbacks.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NRobert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The address of IPv6 raw sockets was shown in the wrong format, from
IPv4 ones.  The problem has been introduced by the commit
42a73808 ("[RAW]: Consolidate proc
interface.")

Thanks to Adrian Bunk who originally noticed the problem.
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There is no need to use 128 bytes on the stack at all. Clean the code
in the IPv6 style.
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Different hashtables are used for IPv6 and IPv4 raw sockets, so no
need to check the socket family in the iterator over hashtables. Clean
this out.
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A userspace program may wish to set the mark for each packets its send
without using the netfilter MARK target. Changing the mark can be used
for mark based routing without netfilter or for packet filtering.

It requires CAP_NET_ADMIN capability.
Signed-off-by: NLaszlo Attila Toth <panther@balabit.hu>
Acked-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Needed to propagate it down to the __ip_route_output_key.

Signed_off_by: Denis V. Lunev <den@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

To do so, just register the proper subsystem and create files in
->init callbacks.

No other special per-namespace handling for raw sockets is required.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Happily, in all the rest places (->bind callbacks only), that require the
struct net, we have a socket, so get the net from it.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pull the struct net pointer up to the showing functions
to filter the sockets depending on their namespaces.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This requires just to pass the appropriate struct net pointer
into __raw_v[46]_lookup and skip sockets that do not belong
to a needed namespace.

The proper net is get from skb->dev in all the cases.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The patch extends the inet_addr_type and inet_dev_addr_type with the
network namespace pointer. That allows to access the different tables
relatively to the network namespace.

The modification of the signature function is reported in all the
callers of the inet_addr_type using the pointer to the well known
init_net.
Acked-by: NBenjamin Thery <benjamin.thery@bull.net>
Acked-by: NDaniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NEric Dumazet <dada1@cosmosbay.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Both ipv6/raw.c and ipv4/raw.c use the seq files to walk
through the raw sockets hash and show them.

The "walking" code is rather huge, but is identical in both
cases. The difference is the hash table to walk over and
the protocol family to check (this was not in the first
virsion of the patch, which was noticed by YOSHIFUJI)

Make the ->open store the needed hash table and the family
on the allocated raw_iter_state and make the start/next/stop
callbacks work with it.

This removes most of the code.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Same as the ->hash one, this is easily consolidated.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Having the raw_hashinfo it's easy to consolidate the
raw[46]_hash functions.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The ipv4/raw.c and ipv6/raw.c contain many common code (most
of which is proc interface) which can be consolidated.

Most of the places to consolidate deal with the raw sockets
hashtable, so introduce a struct raw_hashinfo which describes
the raw sockets hash.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The raw sockets functions are explicitly used from
inside the kernel in two places:

1. in ip_local_deliver_finish to intercept skb-s
2. in icmp_error

For this purposes many functions and even data structures,
that are naturally internal for raw protocol, are exported.

Compact the API to two functions and hide all the other
(including hash table and rwlock) inside the net/ipv4/raw.c
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The IPv4 and IPv6 hook values are identical, yet some code tries to figure
out the "correct" value by looking at the address family. Introduce NF_INET_*
values for both IPv4 and IPv6. The old values are kept in a #ifndef __KERNEL__
section for userspace compatibility.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Acked-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add raw drops counter for IPv4 in /proc/net/raw .
Signed-off-by: NWang Chen <wangchen@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We currently check that iph->ihl is bounded by the real length and that
the real length is greater than the minimum IP header length.  However,
we did not check the caes where iph->ihl is less than the minimum IP
header length.

This breaks because some ip_fast_csum implementations assume that which
is quite reasonable.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>