Commit Graph

145 Commits

Author SHA1 Message Date
Linus Torvalds
92e52b2e82 Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 2005-08-08 16:06:01 -07:00
Heikki Orsila
ca9334523c [IPV4]: Debug cleanup
Here's a small patch to cleanup NETDEBUG() use in net/ipv4/ for Linux 
kernel 2.6.13-rc5. Also weird use of indentation is changed in some
places.

Signed-off-by: Heikki Orsila <heikki.orsila@iki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-08 14:26:52 -07:00
Harald Welte
8b83bc77bf [PATCH] don't try to do any NAT on untracked connections
With the introduction of 'rustynat' in 2.6.11, the old tricks of preventing
NAT of 'untracked' connections (e.g. NOTRACK target in 'raw' table) are no
longer sufficient.

The ip_conntrack_untracked.status |= IPS_NAT_DONE_MASK effectively
prevents iteration of the 'nat' table, but doesn't prevent nat_packet()
to be executed.  Since nr_manips is gone in 'rustynat', nat_packet() now
implicitly thinks that it has to do NAT on the packet.

This patch fixes that problem by explicitly checking for
ip_conntrack_untracked in ip_nat_fn().

Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-08 11:48:28 -07:00
Herbert Xu
6fc0b4a7a7 [IPSEC]: Restrict socket policy loading to CAP_NET_ADMIN.
The interface needs much redesigning if we wish to allow
normal users to do this in some way.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-06 06:33:15 -07:00
David S. Miller
b7656e7f29 [IPV4]: Fix memory leak during fib_info hash expansion.
When we grow the tables, we forget to free the olds ones
up.

Noticed by Yan Zheng.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-05 04:12:48 -07:00
Herbert Xu
b68e9f8572 [PATCH] tcp: fix TSO cwnd caching bug
tcp_write_xmit caches the cwnd value indirectly in cwnd_quota.  When
tcp_transmit_skb reduces the cwnd because of tcp_enter_cwr, the cached
value becomes invalid.

This patch ensures that the cwnd value is always reread after each
tcp_transmit_skb call.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-04 21:43:14 -07:00
David S. Miller
846998ae87 [PATCH] tcp: fix TSO sizing bugs
MSS changes can be lost since we preemptively initialize the tso_segs count
for an SKB before we %100 commit to sending it out.

So, by the time we send it out, the tso_size information can be stale due
to PMTU events.  This mucks up all of the logic in our send engine, and can
even result in the BUG() triggering in tcp_tso_should_defer().

Another problem we have is that we're storing the tp->mss_cache, not the
SACK block normalized MSS, as the tso_size.  That's wrong too.

Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-04 21:43:14 -07:00
Alexey Kuznetsov
db44575f6f [NET]: fix oops after tunnel module unload
Tunnel modules used to obtain module refcount each time when
some tunnel was created, which meaned that tunnel could be unloaded
only after all the tunnels are deleted.

Since killing old MOD_*_USE_COUNT macros this protection has gone.
It is possible to return it back as module_get/put, but it looks
more natural and practically useful to force destruction of all
the child tunnels on module unload.

Signed-off-by: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-30 17:46:44 -07:00
Harald Welte
1f494c0e04 [NETFILTER] Inherit masq_index to slave connections
masq_index is used for cleanup in case the interface address changes
(such as a dialup ppp link with dynamic addreses).  Without this patch,
slave connections are not evicted in such a case, since they don't inherit
masq_index.

Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-30 17:44:07 -07:00
Baruch Even
d1b04c081e [NET]: Spelling mistakes threshoulds -> thresholds
Just simple spelling mistake fixes.

Signed-Off-By: Baruch Even <baruch@ev-en.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-30 17:41:59 -07:00
Matt Mackall
5e43db7730 [NET]: Move in_aton from net/ipv4/utils.c to net/core/utils.c
Move in_aton to allow netpoll and pktgen to work without the rest of
the IPv4 stack. Fix whitespace and add comment for the odd placement.

Delete now-empty net/ipv4/utils.c

Re-enable netpoll/netconsole without CONFIG_INET

Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-27 15:24:42 -07:00
Nick Sillik
7cee432a22 [NETFILTER]: Fix -Wunder error in ip_conntrack_core.c
Signed-off-by: Nick Sillik <n.sillik@temple.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-27 14:46:03 -07:00
Hans-Juergen Tappe (SYSGO AG)
eaa1c5d059 [IPV4]: Fix Kconfig syntax error
From: "Hans-Juergen Tappe (SYSGO AG)" <hjt@sysgo.com>

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-27 13:00:04 -07:00
Patrick McHardy
74bb421da7 [NETFILTER]: Use correct byteorder in ICMP NAT
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-22 12:51:38 -07:00
Patrick McHardy
21f930e4ab [NETFILTER]: Wait until all references to ip_conntrack_untracked are dropped on unload
Fixes a crash when unloading ip_conntrack.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-22 12:51:03 -07:00
Patrick McHardy
d04b4f8c1c [NETFILTER]: Fix potential memory corruption in NAT code (aka memory NAT)
The portptr pointing to the port in the conntrack tuple is declared static,
which could result in memory corruption when two packets of the same
protocol are NATed at the same time and one conntrack goes away.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-22 12:50:29 -07:00
Rusty Russell
4acdbdbe50 [NETFILTER]: ip_conntrack_expect_related must not free expectation
If a connection tracking helper tells us to expect a connection, and
we're already expecting that connection, we simply free the one they
gave us and return success.

The problem is that NAT helpers (eg. FTP) have to allocate the
expectation first (to see what port is available) then rewrite the
packet.  If that rewrite fails, they try to remove the expectation,
but it was freed in ip_conntrack_expect_related.

This is one example of a larger problem: having registered the
expectation, the pointer is no longer ours to use.  Reference counting
is needed for ctnetlink anyway, so introduce it now.

To have a single "put" path, we need to grab the reference to the
connection on creation, rather than open-coding it in the caller.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-21 13:14:46 -07:00
Patrick McHardy
0303770deb [NET]: Make ipip/ip6_tunnel independant of XFRM
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-19 14:03:34 -07:00
Stephen Hemminger
c877efb207 [IPV4]: Fix up lots of little whitespace indentation stuff in fib_trie.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-19 14:01:51 -07:00
Patrick McHardy
abaacad9bc [IPV4]: Don't select XFRM for ip_gre
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-19 13:59:17 -07:00
Adrian Bunk
6876f95f20 [IPV4]: fix IP_FIB_HASH kconfig warning
This patch fixes the following kconfig warning:
  net/ipv4/Kconfig:92:warning: defaults for choice values not supported

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-18 13:55:19 -07:00
Phil Oester
84531c24f2 [NETFILTER]: Revert nf_reset change
Revert the nf_reset change that caused so much trouble, drop conntrack
references manually before packets are queued to packet sockets.

Signed-off-by: Phil Oester <kernel@linuxace.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-12 11:57:52 -07:00
Sam Ravnborg
6a2e9b738c [NET]: move config options out to individual protocols
Move the protocol specific config options out to the specific protocols.
With this change net/Kconfig now starts to become readable and serve as a
good basis for further re-structuring.

The menu structure is left almost intact, except that indention is
fixed in most cases. Most visible are the INET changes where several
"depends on INET" are replaced with a single ifdef INET / endif pair.

Several new files were created to accomplish this change - they are
small but serve the purpose that config options are now distributed
out where they belongs.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-11 21:13:56 -07:00
Olaf Kirch
0b7f22aab4 [IPV4]: Prevent oops when printing martian source
In some cases, we may be generating packets with a source address that
qualifies as martian. This can happen when we're in the middle of setting
up the network, and netfilter decides to reject a packet with an RST.
The IPv4 routing code would try to print a warning and oops, because
locally generated packets do not have a valid skb->mac.raw pointer
at this point.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-11 21:01:42 -07:00
Julian Anastasov
af9debd461 [IPVS]: Add and reorder bh locks after moving to keventd.
An addition to the last ipvs changes that move
update_defense_level/si_meminfo to keventd:

- ip_vs_random_dropentry now runs in process context and should use _bh
  locks to protect from softirqs

- update_defense_level still needs _bh locks after si_meminfo is called,
  for the same purpose

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-11 20:59:57 -07:00
David L Stevens
84b42baef7 [IPV4]: fix IPv4 leave-group group matching
This patch fixes the multicast group matching for 
IP_DROP_MEMBERSHIP, similar to the IP_ADD_MEMBERSHIP fix in a prior
patch. Groups are identifiedby <group address,interface> and including
the interface address in the match will fail if a leave-group is done
by address when the join was done by index, or if different addresses
on the same interface are used in the join and leave.

Signed-off-by: David L Stevens <dlstevens@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-08 17:48:38 -07:00
David L Stevens
9951f036fe [IPV4]: (INCLUDE,empty)/leave-group equivalence for full-state MSF APIs & errno fix
1) Adds (INCLUDE, empty)/leave-group equivalence to the full-state 
   multicast source filter APIs (IPv4 and IPv6)

2) Fixes an incorrect errno in the IPv6 leave-group (ENOENT should be
   EADDRNOTAVAIL)

Signed-off-by: David L Stevens <dlstevens@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-08 17:47:28 -07:00
David L Stevens
917f2f105e [IPV4]: multicast API "join" issues
1) In the full-state API when imsf_numsrc == 0
   errno should be "0", but returns EADDRNOTAVAIL

2) An illegal filter mode change
   errno should be EINVAL, but returns EADDRNOTAVAIL

3) Trying to do an any-source option without IP_ADD_MEMBERSHIP
   errno should be EINVAL, but returns EADDRNOTAVAIL

4) Adds comments for the less obvious error return values

Signed-off-by: David L Stevens <dlstevens@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-08 17:45:16 -07:00
David L Stevens
8cdaaa15da [IPV4]: multicast API "join" issues
1) Changes IP_ADD_SOURCE_MEMBERSHIP and MCAST_JOIN_SOURCE_GROUP to ignore
   EADDRINUSE errors on a "courtesy join" -- prior membership or not
   is ok for these.

2) Adds "leave group" equivalence of (INCLUDE, empty) filters in the 
   delta-based API. Without this, mixing delta-based API calls that
   end in an (INCLUDE, empty) filter would not allow a subsequent
   regular IP_ADD_MEMBERSHIP. It also frees socket buffer memory that
   isn't needed for both the multicast group record and source filter.

Signed-off-by: David L Stevens <dlstevens@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-08 17:39:23 -07:00
David L Stevens
ca9b907d14 [IPV4]: multicast API "join" issues
This patch corrects a few problems with the IP_ADD_MEMBERSHIP
socket option:

1) The existing code makes an attempt at reference counting joins when
   using the ip_mreqn/imr_ifindex interface. Joining the same group
   on the same socket is an error, whatever the API. This leads to
   unexpected results when mixing ip_mreqn by index with ip_mreqn by
   address, ip_mreq, or other API's. For example, ip_mreq followed by
   ip_mreqn of the same group will "work" while the same two reversed
   will not.
           Fixed to always return EADDRINUSE on a duplicate join and
   removed the (now unused) reference count in ip_mc_socklist.

2) The group-search list in ip_mc_join_group() is comparing a full 
   ip_mreqn structure and all of it must match for it to find the
   group. This doesn't correctly match a group that was joined with
   ip_mreq or ip_mreqn with an address (with or without an index). It
   also doesn't match groups that are joined by different addresses on
   the same interface. All of these are the same multicast group,
   which is identified by group address and interface index.
           Fixed the check to correctly match groups so we don't get
   duplicate group entries on the ip_mc_socklist.

3) The old code allocates a multicast address before searching for
   duplicates requiring it to free in various error cases. This
   patch moves the allocate until after the search and
   igmp_max_memberships check, so never a need to allocate, then free
   an entry.

Signed-off-by: David L Stevens <dlstevens@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-08 17:38:07 -07:00
Alexey Kuznetsov
4c866aa798 [IPV4]: Apply sysctl_icmp_echo_ignore_broadcasts to ICMP_TIMESTAMP as well.
This was the full intention of the original code.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-08 17:34:46 -07:00
Victor Fusco
86a76caf87 [NET]: Fix sparse warnings
From: Victor Fusco <victor@cetuc.puc-rio.br>

Fix the sparse warning "implicit cast to nocast type"

Signed-off-by: Victor Fusco <victor@cetuc.puc-rio.br>
Signed-off-by: Domen Puncer <domen@coderock.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-08 14:57:47 -07:00
David S. Miller
b03efcfb21 [NET]: Transform skb_queue_len() binary tests into skb_queue_empty()
This is part of the grand scheme to eliminate the qlen
member of skb_queue_head, and subsequently remove the
'list' member of sk_buff.

Most users of skb_queue_len() want to know if the queue is
empty or not, and that's trivially done with skb_queue_empty()
which doesn't use the skb_queue_head->qlen member and instead
uses the queue list emptyness as the test.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-08 14:57:23 -07:00
David S. Miller
908a75c17a [TCP]: Never TSO defer under periods of congestion.
Congestion window recover after loss depends upon the fact
that if we have a full MSS sized frame at the head of the
send queue, we will send it.  TSO deferral can defeat the
ACK clocking necessary to exit cleanly from recovery.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 15:43:58 -07:00
David S. Miller
c1b4a7e695 [TCP]: Move to new TSO segmenting scheme.
Make TSO segment transmit size decisions at send time not earlier.

The basic scheme is that we try to build as large a TSO frame as
possible when pulling in the user data, but the size of the TSO frame
output to the card is determined at transmit time.

This is guided by tp->xmit_size_goal.  It is always set to a multiple
of MSS and tells sendmsg/sendpage how large an SKB to try and build.

Later, tcp_write_xmit() and tcp_push_one() chop up the packet if
necessary and conditions warrant.  These routines can also decide to
"defer" in order to wait for more ACKs to arrive and thus allow larger
TSO frames to be emitted.

A general observation is that TSO elongates the pipe, thus requiring a
larger congestion window and larger buffering especially at the sender
side.  Therefore, it is important that applications 1) get a large
enough socket send buffer (this is accomplished by our dynamic send
buffer expansion code) 2) do large enough writes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 15:24:38 -07:00
David S. Miller
0d9901df62 [TCP]: Break out send buffer expansion test.
This makes it easier to understand, and allows easier
tweaking of the heuristic later on.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 15:21:10 -07:00
David S. Miller
cb83199a29 [TCP]: Do not call tcp_tso_acked() if no work to do.
In tcp_clean_rtx_queue(), if the TSO packet is not even partially
acked, do not waste time calling tcp_tso_acked().

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 15:20:55 -07:00
David S. Miller
a56476962e [TCP]: Kill bogus comment above tcp_tso_acked().
Everything stated there is out of data.  tcp_trim_skb()
does adjust the available socket send buffer space and
skb->truesize now.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 15:20:41 -07:00
David S. Miller
b4e26f5ea0 [TCP]: Fix send-side cpu utiliziation regression.
Only put user data purely to pages when doing TSO.

The extra page allocations cause two problems:

1) Add the overhead of the page allocations themselves.
2) Make us do small user copies when we get to the end
   of the TCP socket cache page.

It is still beneficial to purely use pages for TSO,
so we will do it for that case.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 15:20:27 -07:00
David S. Miller
aa93466bdf [TCP]: Eliminate redundant computations in tcp_write_xmit().
tcp_snd_test() is run for every packet output by a single
call to tcp_write_xmit(), but this is not necessary.

For one, the congestion window space needs to only be
calculated one time, then used throughout the duration
of the loop.

This cleanup also makes experimenting with different TSO
packetization schemes much easier.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 15:20:09 -07:00
David S. Miller
7f4dd0a943 [TCP]: Break out tcp_snd_test() into it's constituent parts.
tcp_snd_test() does several different things, use inline
functions to express this more clearly.

1) It initializes the TSO count of SKB, if necessary.
2) It performs the Nagle test.
3) It makes sure the congestion window is adhered to.
4) It makes sure SKB fits into the send window.

This cleanup also sets things up so that things like the
available packets in the congestion window does not need
to be calculated multiple times by packet sending loops
such as tcp_write_xmit().
    
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 15:19:54 -07:00
David S. Miller
55c97f3e99 [TCP]: Fix __tcp_push_pending_frames() 'nonagle' handling.
'nonagle' should be passed to the tcp_snd_test() function
as 'TCP_NAGLE_PUSH' if we are checking an SKB not at the
tail of the write_queue.  This is because Nagle does not
apply to such frames since we cannot possibly tack more
data onto them.

However, while doing this __tcp_push_pending_frames() makes
all of the packets in the write_queue use this modified
'nonagle' value.

Fix the bug and simplify this function by just calling
tcp_write_xmit() directly if sk_send_head is non-NULL.

As a result, we can now make tcp_data_snd_check() just call
tcp_push_pending_frames() instead of the specialized
__tcp_data_snd_check().

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 15:19:38 -07:00
David S. Miller
a2e2a59c93 [TCP]: Fix redundant calculations of tcp_current_mss()
tcp_write_xmit() uses tcp_current_mss(), but some of it's callers,
namely __tcp_push_pending_frames(), already has this value available
already.

While we're here, fix the "cur_mss" argument to be "unsigned int"
instead of plain "unsigned".

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 15:19:23 -07:00
David S. Miller
92df7b518d [TCP]: tcp_write_xmit() tabbing cleanup
Put the main basic block of work at the top-level of
tabbing, and mark the TCP_CLOSE test with unlikely().

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 15:19:06 -07:00
David S. Miller
a762a98007 [TCP]: Kill extra cwnd validate in __tcp_push_pending_frames().
The tcp_cwnd_validate() function should only be invoked
if we actually send some frames, yet __tcp_push_pending_frames()
will always invoke it.  tcp_write_xmit() does the call for us,
so the call here can simply be removed.

Also, tcp_write_xmit() can be marked static.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 15:18:51 -07:00
David S. Miller
f44b527177 [TCP]: Add missing skb_header_release() call to tcp_fragment().
When we add any new packet to the TCP socket write queue,
we must call skb_header_release() on it in order for the
TSO sharing checks in the drivers to work.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 15:18:34 -07:00
David S. Miller
84d3e7b957 [TCP]: Move __tcp_data_snd_check into tcp_output.c
It reimplements portions of tcp_snd_check(), so it
we move it to tcp_output.c we can consolidate it's
logic much easier in a later change.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 15:18:18 -07:00
David S. Miller
f6302d1d78 [TCP]: Move send test logic out of net/tcp.h
This just moves the code into tcp_output.c, no code logic changes are
made by this patch.

Using this as a baseline, we can begin to untangle the mess of
comparisons for the Nagle test et al.  We will also be able to reduce
all of the redundant computation that occurs when outputting data
packets.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 15:18:03 -07:00
David S. Miller
fc6415bcb0 [TCP]: Fix quick-ack decrementing with TSO.
On each packet output, we call tcp_dec_quickack_mode()
if the ACK flag is set.  It drops tp->ack.quick until
it hits zero, at which time we deflate the ATO value.

When doing TSO, we are emitting multiple packets with
ACK set, so we should decrement tp->ack.quick that many
segments.

Note that, unlike this case, tcp_enter_cwr() should not
take the tcp_skb_pcount(skb) into consideration.  That
function, one time, readjusts tp->snd_cwnd and moves
into TCP_CA_CWR state.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 15:17:45 -07:00
David S. Miller
c65f7f00c5 [TCP]: Simplify SKB data portion allocation with NETIF_F_SG.
The ideal and most optimal layout for an SKB when doing
scatter-gather is to put all the headers at skb->data, and
all the user data in the page array.

This makes SKB splitting and combining extremely simple,
especially before a packet goes onto the wire the first
time.

So, when sk_stream_alloc_pskb() is given a zero size, make
sure there is no skb_tailroom().  This is achieved by applying
SKB_DATA_ALIGN() to the header length used here.

Next, make select_size() in TCP output segmentation use a
length of zero when NETIF_F_SG is true on the outgoing
interface.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 15:17:25 -07:00