<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/net/ipv4/ip_output.c, branch v2.6.38</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>ipv4: Don't pre-seed hoplimit metric.</title>
<updated>2010-12-13T06:08:17+00:00</updated>
<author>
<name>David S. Miller</name>
<email>davem@davemloft.net</email>
</author>
<published>2010-12-13T05:55:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=323e126f0c5995f779d7df7fd035f6e8fed8764d'/>
<id>323e126f0c5995f779d7df7fd035f6e8fed8764d</id>
<content type='text'>
Always go through a new ip4_dst_hoplimit() helper, just like ipv6.

This allowed several simplifications:

1) The interim dst_metric_hoplimit() can go as it's no longer
   userd.

2) The sysctl_ip_default_ttl entry no longer needs to use
   ipv4_doint_and_flush, since the sysctl is not cached in
   routing cache metrics any longer.

3) ipv4_doint_and_flush no longer needs to be exported and
   therefore can be marked static.

When ipv4_doint_and_flush_strategy was removed some time ago,
the external declaration in ip.h was mistakenly left around
so kill that off too.

We have to move the sysctl_ip_default_ttl declaration into
ipv4's route cache definition header net/route.h, because
currently net/ip.h (where the declaration lives now) has
a back dependency on net/route.h

Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Always go through a new ip4_dst_hoplimit() helper, just like ipv6.

This allowed several simplifications:

1) The interim dst_metric_hoplimit() can go as it's no longer
   userd.

2) The sysctl_ip_default_ttl entry no longer needs to use
   ipv4_doint_and_flush, since the sysctl is not cached in
   routing cache metrics any longer.

3) ipv4_doint_and_flush no longer needs to be exported and
   therefore can be marked static.

When ipv4_doint_and_flush_strategy was removed some time ago,
the external declaration in ip.h was mistakenly left around
so kill that off too.

We have to move the sysctl_ip_default_ttl declaration into
ipv4's route cache definition header net/route.h, because
currently net/ip.h (where the declaration lives now) has
a back dependency on net/route.h

Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: Abstract RTAX_HOPLIMIT metric accesses behind helper.</title>
<updated>2010-12-13T05:35:57+00:00</updated>
<author>
<name>David S. Miller</name>
<email>davem@davemloft.net</email>
</author>
<published>2010-12-13T05:35:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=5170ae824ddf1988a63fb12cbedcff817634c444'/>
<id>5170ae824ddf1988a63fb12cbedcff817634c444</id>
<content type='text'>
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: use the macros defined for the members of flowi</title>
<updated>2010-11-17T20:27:45+00:00</updated>
<author>
<name>Changli Gao</name>
<email>xiaosuo@gmail.com</email>
</author>
<published>2010-11-12T18:43:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=5811662b15db018c740c57d037523683fd3e6123'/>
<id>5811662b15db018c740c57d037523683fd3e6123</id>
<content type='text'>
Use the macros defined for the members of flowi to clean the code up.

Signed-off-by: Changli Gao &lt;xiaosuo@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Use the macros defined for the members of flowi to clean the code up.

Signed-off-by: Changli Gao &lt;xiaosuo@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6</title>
<updated>2010-09-27T08:03:03+00:00</updated>
<author>
<name>David S. Miller</name>
<email>davem@davemloft.net</email>
</author>
<published>2010-09-27T08:03:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=e40051d134f7ee95c8c1f7a3471e84eafc9ab326'/>
<id>e40051d134f7ee95c8c1f7a3471e84eafc9ab326</id>
<content type='text'>
Conflicts:
	drivers/net/qlcnic/qlcnic_init.c
	net/ipv4/ip_output.c
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Conflicts:
	drivers/net/qlcnic/qlcnic_init.c
	net/ipv4/ip_output.c
</pre>
</div>
</content>
</entry>
<entry>
<title>ip: take care of last fragment in ip_append_data</title>
<updated>2010-09-24T21:41:04+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>eric.dumazet@gmail.com</email>
</author>
<published>2010-09-20T20:16:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=59104f062435c7816e39ee5ed504a69cb8037f10'/>
<id>59104f062435c7816e39ee5ed504a69cb8037f10</id>
<content type='text'>
While investigating a bit, I found ip_fragment() slow path was taken
because ip_append_data() provides following layout for a send(MTU +
N*(MTU - 20)) syscall :

- one skb with 1500 (mtu) bytes
- N fragments of 1480 (mtu-20) bytes (before adding IP header)
last fragment gets 17 bytes of trail data because of following bit:

	if (datalen == length + fraggap)
		alloclen += rt-&gt;dst.trailer_len;

Then esp4 adds 16 bytes of data (while trailer_len is 17... hmm...
another bug ?)

In ip_fragment(), we notice last fragment is too big (1496 + 20) &gt; mtu,
so we take slow path, building another skb chain.

In order to avoid taking slow path, we should correct ip_append_data()
to make sure last fragment has real trail space, under mtu...

Signed-off-by: Eric Dumazet &lt;eric.dumazet@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
While investigating a bit, I found ip_fragment() slow path was taken
because ip_append_data() provides following layout for a send(MTU +
N*(MTU - 20)) syscall :

- one skb with 1500 (mtu) bytes
- N fragments of 1480 (mtu-20) bytes (before adding IP header)
last fragment gets 17 bytes of trail data because of following bit:

	if (datalen == length + fraggap)
		alloclen += rt-&gt;dst.trailer_len;

Then esp4 adds 16 bytes of data (while trailer_len is 17... hmm...
another bug ?)

In ip_fragment(), we notice last fragment is too big (1496 + 20) &gt; mtu,
so we take slow path, building another skb chain.

In order to avoid taking slow path, we should correct ip_append_data()
to make sure last fragment has real trail space, under mtu...

Signed-off-by: Eric Dumazet &lt;eric.dumazet@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ip: fix truesize mismatch in ip fragmentation</title>
<updated>2010-09-21T22:05:50+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>eric.dumazet@gmail.com</email>
</author>
<published>2010-09-21T08:47:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=3d13008e7345fa7a79d8f6438150dc15d6ba6e9d'/>
<id>3d13008e7345fa7a79d8f6438150dc15d6ba6e9d</id>
<content type='text'>
Special care should be taken when slow path is hit in ip_fragment() :

When walking through frags, we transfert truesize ownership from skb to
frags. Then if we hit a slow_path condition, we must undo this or risk
uncharging frags-&gt;truesize twice, and in the end, having negative socket
sk_wmem_alloc counter, or even freeing socket sooner than expected.

Many thanks to Nick Bowler, who provided a very clean bug report and
test program.

Thanks to Jarek for reviewing my first patch and providing a V2

While Nick bisection pointed to commit 2b85a34e911 (net: No more
expensive sock_hold()/sock_put() on each tx), underlying bug is older
(2.6.12-rc5)

A side effect is to extend work done in commit b2722b1c3a893e
(ip_fragment: also adjust skb-&gt;truesize for packets not owned by a
socket) to ipv6 as well.

Reported-and-bisected-by: Nick Bowler &lt;nbowler@elliptictech.com&gt;
Tested-by: Nick Bowler &lt;nbowler@elliptictech.com&gt;
Signed-off-by: Eric Dumazet &lt;eric.dumazet@gmail.com&gt;
CC: Jarek Poplawski &lt;jarkao2@gmail.com&gt;
CC: Patrick McHardy &lt;kaber@trash.net&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Special care should be taken when slow path is hit in ip_fragment() :

When walking through frags, we transfert truesize ownership from skb to
frags. Then if we hit a slow_path condition, we must undo this or risk
uncharging frags-&gt;truesize twice, and in the end, having negative socket
sk_wmem_alloc counter, or even freeing socket sooner than expected.

Many thanks to Nick Bowler, who provided a very clean bug report and
test program.

Thanks to Jarek for reviewing my first patch and providing a V2

While Nick bisection pointed to commit 2b85a34e911 (net: No more
expensive sock_hold()/sock_put() on each tx), underlying bug is older
(2.6.12-rc5)

A side effect is to extend work done in commit b2722b1c3a893e
(ip_fragment: also adjust skb-&gt;truesize for packets not owned by a
socket) to ipv6 as well.

Reported-and-bisected-by: Nick Bowler &lt;nbowler@elliptictech.com&gt;
Tested-by: Nick Bowler &lt;nbowler@elliptictech.com&gt;
Signed-off-by: Eric Dumazet &lt;eric.dumazet@gmail.com&gt;
CC: Jarek Poplawski &lt;jarkao2@gmail.com&gt;
CC: Patrick McHardy &lt;kaber@trash.net&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: ip_append_data() optim</title>
<updated>2010-08-24T21:45:09+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>eric.dumazet@gmail.com</email>
</author>
<published>2010-08-24T21:45:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=ec550d246e38e1b4ea8604b5c71ccb72e38f3290'/>
<id>ec550d246e38e1b4ea8604b5c71ccb72e38f3290</id>
<content type='text'>
Compiler is not smart enough to avoid a conditional branch.

Signed-off-by: Eric Dumazet &lt;eric.dumazet@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Compiler is not smart enough to avoid a conditional branch.

Signed-off-by: Eric Dumazet &lt;eric.dumazet@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: Rename skb_has_frags to skb_has_frag_list</title>
<updated>2010-08-23T07:13:46+00:00</updated>
<author>
<name>David S. Miller</name>
<email>davem@davemloft.net</email>
</author>
<published>2010-08-23T07:13:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=21dc330157454046dd7c494961277d76e1c957fe'/>
<id>21dc330157454046dd7c494961277d76e1c957fe</id>
<content type='text'>
SKBs can be "fragmented" in two ways, via a page array (called
skb_shinfo(skb)-&gt;frags[]) and via a list of SKBs (called
skb_shinfo(skb)-&gt;frag_list).

Since skb_has_frags() tests the latter, it's name is confusing
since it sounds more like it's testing the former.

Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
SKBs can be "fragmented" in two ways, via a page array (called
skb_shinfo(skb)-&gt;frags[]) and via a list of SKBs (called
skb_shinfo(skb)-&gt;frag_list).

Since skb_has_frags() tests the latter, it's name is confusing
since it sounds more like it's testing the former.

Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: simplify flags for tx timestamping</title>
<updated>2010-08-19T07:08:30+00:00</updated>
<author>
<name>Oliver Hartkopp</name>
<email>socketcan@hartkopp.net</email>
</author>
<published>2010-08-17T08:59:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=2244d07bfa2097cb00600da91c715a8aa547917e'/>
<id>2244d07bfa2097cb00600da91c715a8aa547917e</id>
<content type='text'>
This patch removes the abstraction introduced by the union skb_shared_tx in
the shared skb data.

The access of the different union elements at several places led to some
confusion about accessing the shared tx_flags e.g. in skb_orphan_try().

    http://marc.info/?l=linux-netdev&amp;m=128084897415886&amp;w=2

Signed-off-by: Oliver Hartkopp &lt;socketcan@hartkopp.net&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This patch removes the abstraction introduced by the union skb_shared_tx in
the shared skb data.

The access of the different union elements at several places led to some
confusion about accessing the shared tx_flags e.g. in skb_orphan_try().

    http://marc.info/?l=linux-netdev&amp;m=128084897415886&amp;w=2

Signed-off-by: Oliver Hartkopp &lt;socketcan@hartkopp.net&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ip_fragment: fix subtracting PPPOE_SES_HLEN from mtu twice</title>
<updated>2010-08-03T00:25:07+00:00</updated>
<author>
<name>Changli Gao</name>
<email>xiaosuo@gmail.com</email>
</author>
<published>2010-07-31T13:25:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=c893b8066c7bf6156e4d760e5acaf4c148e37190'/>
<id>c893b8066c7bf6156e4d760e5acaf4c148e37190</id>
<content type='text'>
6c79bf0f2440fd250c8fce8d9b82fcf03d4e8350 subtracts PPPOE_SES_HLEN from mtu at
the front of ip_fragment(). So the later subtraction should be removed. The
MTU of 802.1q is also 1500, so MTU should not be changed.

Signed-off-by: Changli Gao &lt;xiaosuo@gmail.com&gt;
Signed-off-by: Bart De Schuymer &lt;bdschuym@pandora.bo&gt;
----
 net/ipv4/ip_output.c |    6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)
Signed-off-by: Bart De Schuymer &lt;bdschuym@pandora.bo&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
6c79bf0f2440fd250c8fce8d9b82fcf03d4e8350 subtracts PPPOE_SES_HLEN from mtu at
the front of ip_fragment(). So the later subtraction should be removed. The
MTU of 802.1q is also 1500, so MTU should not be changed.

Signed-off-by: Changli Gao &lt;xiaosuo@gmail.com&gt;
Signed-off-by: Bart De Schuymer &lt;bdschuym@pandora.bo&gt;
----
 net/ipv4/ip_output.c |    6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)
Signed-off-by: Bart De Schuymer &lt;bdschuym@pandora.bo&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
</feed>
