Commit Graph

78011 Commits

Author SHA1 Message Date
Benjamin Thery
3ef1355dcb [NET]: Make netns cleanup to run in a separate queue
This patch adds a separate workqueue for cleaning up a network
namespace. If we use the keventd workqueue to execute cleanup_net(),
there is a problem to unregister devices in IPv6. Indeed the code
that cleans up also schedule work in keventd: as long as cleanup_net()
hasn't return, dst_gc_task() cannot run and as long as dst_gc_task() has
not run, there are still some references pending on the net devices and
cleanup_net() can not unregister and exit the keventd workqueue.

Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Acked-by: Denis V. Lunev <den@openvz.org>
Acked-By: Kirill Korotaev <dev@sw.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:35 -08:00
Pavel Emelyanov
85b606800b [IPVS]: Relax the module get/put in ip_vs_app.c
Both try_module_get/module_put already handle the module == NULL
case, so no need in manual checking.

This patch fits both net-2.6 and net-2.6.25.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:35 -08:00
Akinobu Mita
52427c9d11 [TUN]: Use iov_length()
Use iov_length() instead of tun's homemade iov_total().

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:34 -08:00
Adrian Bunk
02d45827fa [NET] net/core/request_sock.c: Remove unused exports.
This patch removes the following unused EXPORT_SYMBOL's:
- reqsk_queue_alloc
- __reqsk_queue_destroy
- reqsk_queue_destroy

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:33 -08:00
Eric Dumazet
beb659bd8c [PATCH] IPV4 : Move ip route cache flush (secret_rebuild) from softirq to workqueue
Every 600 seconds (ip_rt_secret_interval), a softirq flush of the
whole ip route cache is triggered. On loaded machines, this can starve
softirq for many seconds and can eventually crash.

This patch moves this flush to a workqueue context, using the worker
we intoduced in commit 39c90ece75 (IPV4:
Convert rt_check_expire() from softirq processing to workqueue.)

Also, immediate flushes (echo 0 >/proc/sys/net/ipv4/route/flush) are
using rt_do_flush() helper function, wich take attention to
rescheduling.

Next step will be to handle delayed flushes
("echo -1 >/proc/sys/net/ipv4/route/flush" or "ip route flush cache")

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:33 -08:00
Pavel Emelyanov
42a73808ed [RAW]: Consolidate proc interface.
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: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:32 -08:00
Pavel Emelyanov
ab70768ec7 [RAW]: Consolidate proto->unhash callback
Same as the ->hash one, this is easily consolidated.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:31 -08:00
Pavel Emelyanov
65b4c50b47 [RAW]: Consolidate proto->hash callback
Having the raw_hashinfo it's easy to consolidate the
raw[46]_hash functions.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:31 -08:00
Pavel Emelyanov
b673e4dfc8 [RAW]: Introduce raw_hashinfo structure
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: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:30 -08:00
Pavel Emelyanov
69d6da0b0f [IPv6] RAW: Compact the API for the kernel
Same as in the previous patch for ipv4, compact the
API and hide hash table and rwlock inside the raw.c
file.

Plus fix some "bad" places from checkpatch.pl point
of view (assignments inside if()).

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:29 -08:00
Pavel Emelyanov
7bc54c9030 [IPv4] RAW: Compact the API for the kernel
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: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:28 -08:00
Denis V. Lunev
e372c41401 [NET]: Consolidate net namespace related proc files creation.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:28 -08:00
Denis V. Lunev
097e66c578 [NET]: Make AF_UNIX per network namespace safe [v2]
Because of the global nature of garbage collection, and because of the
cost of per namespace hash tables unix_socket_table has been kept
global.  With a filter added on lookups so we don't see sockets from
the wrong namespace.

Currently I don't fold the namesapce into the hash so multiple
namespaces using the same socket name will be guaranteed a hash
collision.

Changes from v1:
- fixed unix_seq_open

Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:27 -08:00
Denis V. Lunev
d12d01d6b4 [NET]: Make AF_PACKET handle multiple network namespaces
This is done by making packet_sklist_lock and packet_sklist per
network namespace and adding an additional filter condition on
received packets to ensure they came from the proper network
namespace.

Changes from v1:
- prohibit to call inet_dgram_ops.ioctl in other than init_net

Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:26 -08:00
Eric W. Biederman
4b3da706bb [NET]: Make the netlink methods in rtnetlink handle multiple network namespaces
After the previous prep work this just consists of removing checks
limiting the code to work in the initial network namespace, and
updating rtmsg_ifinfo so we can generate events for devices in
something other then the initial network namespace.

Referring to network other network devices like the IFLA_LINK
and IFLA_MASTER attributes do, gets interesting if those network
devices happen to be in other network namespaces.  Currently
ifindex numbers are allocated globally so I have taken the path
of least resistance and not still report the information even
though the devices they are talking about are invisible.

If applications start getting confused or when ifindex
numbers become local to the network namespace we may need
to do something different in the future.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Denis V. Lunev <den@openz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:26 -08:00
Denis V. Lunev
97c53cacf0 [NET]: Make rtnetlink infrastructure network namespace aware (v3)
After this patch none of the netlink callback support anything
except the initial network namespace but the rtnetlink infrastructure
now handles multiple network namespaces.

Changes from v2:
- IPv6 addrlabel processing

Changes from v1:
- no need for special rtnl_unlock handling
- fixed IPv6 ndisc

Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:25 -08:00
Denis V. Lunev
b854272b3c [NET]: Modify all rtnetlink methods to only work in the initial namespace (v2)
Before I can enable rtnetlink to work in all network namespaces I need
to be certain that something won't break.  So this patch deliberately
disables all of the rtnletlink methods in everything except the
initial network namespace.  After the methods have been audited this
extra check can be disabled.

Changes from v1:
- added IPv6 addrlabel protection

Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-28 14:54:24 -08:00
Patrick McHardy
ad5d20a639 [MACVLAN]: Allow setting mac address while device is up
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:23 -08:00
Patrick McHardy
59891d53f4 [MACVLAN]: Remove unnecessary IFF_UP check
Only devices that are UP are in the hash, so macvlan_broadcast() doesn't
need to check for IFF_UP.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:23 -08:00
David S. Miller
1b0b04f9fb [IPCONFIG]: Mark vendor_class_identifier as __initdata.
Based upon a suggestion by Francois Romieu.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:22 -08:00
Rumen G. Bogdanovski
b209639e8a [IPVS]: Create synced connections with their real state
With this patch the synced connections are created with their real state,
which can be changed on the next synchronizations if necessary. This way
on fail-over all the connections will be treated according to their actual
state, causing no scheduling problems (the active and the nonactive
connections have different weights in the schedulers).
The backwards compatibility is preserved and the existing tools will show
the true connection states even on the backup director.

Signed-off-by: Rumen G. Bogdanovski <rumen@voicecho.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:21 -08:00
Rumen G. Bogdanovski
7a4fbb1fa4 [IPVS]: Flag synced connections and expose them in proc
This patch labels the sync-created connections with IP_VS_CONN_F_SYNC
flag and creates /proc/net/ip_vs_conn_sync to enable monitoring of the
origin of the connections, if they are local or created by the
synchronization.

Signed-off-by: Rumen G. Bogdanovski <rumen@voicecho.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:21 -08:00
Michael Wu
c237899d1f ieee80211: Add IEEE80211_MAX_FRAME_LEN to linux/ieee80211.h
This patch adds IEEE80211_MAX_FRAME_LEN which is useful for drivers trying
to determine how much to allocate for their RX buffers.

It also updates the comment on IEEE80211_MAX_DATA_LEN based on revisions
in 802.11e.

IEEE80211_MAX_FRAG_THRESHOLD and IEEE80211_MAX_RTS_THRESHOLD are also
revised due to the new maximum frame size.

Signed-off-by: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:20 -08:00
Mattias Nissler
6a4329554c mac80211: Accept auto txpower setting
This changes the SIWTXPOWER ioctl to also accept a txpower setting of
"automatic". Since mac80211 currently cannot tell drivers to automatically
adjust tx power, we select the tx power level of the current channel. While
this is kind of a hack, it certainly saves some iwconfig users from headaches.

Signed-off-by: Mattias Nissler <mattias.nissler@gmx.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:19 -08:00
Stephen Hemminger
c7b6ea24b4 [NETPOLL]: Don't need rx_flags.
The rx_flags variable is redundant. Turning rx on/off is done
via setting the rx_np pointer.

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:18 -08:00
Stephen Hemminger
33f807ba0d [NETPOLL]: Kill NETPOLL_RX_DROP, set but never tested.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:18 -08:00
Stephen Hemminger
0953864160 [NETPOLL]: no need to store local_mac
The local_mac is managed by the network device, no need to keep a
spare copy and all the management problems that could cause.

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:17 -08:00
Stephen Hemminger
5106930bd6 [NETPOLL]: netpoll_poll() cleanup
Restructure code slightly to improve readability:
  * dereference device once
  * change obvious while() loop
  * let poll_napi() handle null list itself

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:16 -08:00
Stephen Hemminger
0adc9add77 [NETPOLL]: Use skb_queue_purge().
Use standard routine for flushing queue.

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:16 -08:00
Ilpo Järvinen
20de20beba [TCP]: Correct DSACK check placing
Previously one of the in-block skip branches was missing it.

Also, drop it from tail-fully-processed case because the next
iteration will do exactly the same thing, i.e., process the
SACK block that contains the DSACK information.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:15 -08:00
Oliver Hartkopp
f7ab97f78a [CAN]: Add documentation
This patch adds documentation for the PF_CAN protocol family.

Signed-off-by: Oliver Hartkopp <oliver.hartkopp@volkswagen.de>
Signed-off-by: Urs Thuermann <urs.thuermann@volkswagen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:14 -08:00
Oliver Hartkopp
beca222d1a [CAN]: Add maintainer entries
This patch adds entries in the CREDITS and MAINTAINERS file for CAN.

Signed-off-by: Oliver Hartkopp <oliver.hartkopp@volkswagen.de>
Signed-off-by: Urs Thuermann <urs.thuermann@volkswagen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:14 -08:00
Oliver Hartkopp
1f98eefae8 [CAN]: Add missing Kbuild entries
This patch adds the missing Kbuild entries and the missing Kbuild file
in include/linux/can for the CAN subsystem.

Signed-off-by: Oliver Hartkopp <oliver@hartkopp.net>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:13 -08:00
Oliver Hartkopp
4195e31780 [CAN]: Fix plain integer definitions in userspace header.
This patch fixes the use of plain integers instead of __u32 in a struct
that is visible from kernel space and user space.

Thanks to Sam Ravnborg for pointing out the wrong plain int usage.

Signed-off-by: Oliver Hartkopp <oliver@hartkopp.net>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:12 -08:00
Oliver Hartkopp
ccb2963799 [CAN]: Add virtual CAN netdevice driver
This patch adds the virtual CAN bus (vcan) network driver.
The vcan device is just a loopback device for CAN frames, no
real CAN hardware is involved.

Signed-off-by: Oliver Hartkopp <oliver.hartkopp@volkswagen.de>
Signed-off-by: Urs Thuermann <urs.thuermann@volkswagen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:12 -08:00
Oliver Hartkopp
ffd980f976 [CAN]: Add broadcast manager (bcm) protocol
This patch adds the CAN broadcast manager (bcm) protocol.

Signed-off-by: Oliver Hartkopp <oliver.hartkopp@volkswagen.de>
Signed-off-by: Urs Thuermann <urs.thuermann@volkswagen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:11 -08:00
Oliver Hartkopp
c18ce101f2 [CAN]: Add raw protocol
This patch adds the CAN raw protocol.

Signed-off-by: Oliver Hartkopp <oliver.hartkopp@volkswagen.de>
Signed-off-by: Urs Thuermann <urs.thuermann@volkswagen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:10 -08:00
Oliver Hartkopp
0d66548a10 [CAN]: Add PF_CAN core module
This patch adds the CAN core functionality but no protocols or drivers.
No protocol implementations are included here.  They come as separate
patches.  Protocol numbers are already in include/linux/can.h.

Signed-off-by: Oliver Hartkopp <oliver.hartkopp@volkswagen.de>
Signed-off-by: Urs Thuermann <urs.thuermann@volkswagen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:10 -08:00
Oliver Hartkopp
cd05acfe65 [CAN]: Allocate protocol numbers for PF_CAN
This patch adds a protocol/address family number, ARP hardware type,
ethernet packet type, and a line discipline number for the SocketCAN
implementation.

Signed-off-by: Oliver Hartkopp <oliver.hartkopp@volkswagen.de>
Signed-off-by: Urs Thuermann <urs.thuermann@volkswagen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:09 -08:00
Eric Dumazet
8dbde28d97 [NET]: NET_CLS_ROUTE : convert ip_rt_acct to per_cpu variables
ip_rt_acct needs 4096 bytes per cpu to perform some accounting.
It is actually allocated as a single huge array [4096*NR_CPUS]
(rounded up to a power of two)

Converting it to a per cpu variable is wanted to :
 - Save space on machines were num_possible_cpus() < NR_CPUS
 - Better NUMA placement (each cpu gets memory on its node)

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:08 -08:00
Ilpo Järvinen
68f8353b48 [TCP]: Rewrite SACK block processing & sack_recv_cache use
Key points of this patch are:

  - In case new SACK information is advance only type, no skb
    processing below previously discovered highest point is done
  - Optimize cases below highest point too since there's no need
    to always go up to highest point (which is very likely still
    present in that SACK), this is not entirely true though
    because I'm dropping the fastpath_skb_hint which could
    previously optimize those cases even better. Whether that's
    significant, I'm not too sure.

Currently it will provide skipping by walking. Combined with
RB-tree, all skipping would become fast too regardless of window
size (can be done incrementally later).

Previously a number of cases in TCP SACK processing fails to
take advantage of costly stored information in sack_recv_cache,
most importantly, expected events such as cumulative ACK and new
hole ACKs. Processing on such ACKs result in rather long walks
building up latencies (which easily gets nasty when window is
huge). Those latencies are often completely unnecessary
compared with the amount of _new_ information received, usually
for cumulative ACK there's no new information at all, yet TCP
walks whole queue unnecessary potentially taking a number of
costly cache misses on the way, etc.!

Since the inclusion of highest_sack, there's a lot information
that is very likely redundant (SACK fastpath hint stuff,
fackets_out, highest_sack), though there's no ultimate guarantee
that they'll remain the same whole the time (in all unearthly
scenarios). Take advantage of this knowledge here and drop
fastpath hint and use direct access to highest SACKed skb as
a replacement.

Effectively "special cased" fastpath is dropped. This change
adds some complexity to introduce better coveraged "fastpath",
though the added complexity should make TCP behave more cache
friendly.

The current ACK's SACK blocks are compared against each cached
block individially and only ranges that are new are then scanned
by the high constant walk. For other parts of write queue, even
when in previously known part of the SACK blocks, a faster skip
function is used (if necessary at all). In addition, whenever
possible, TCP fast-forwards to highest_sack skb that was made
available by an earlier patch. In typical case, no other things
but this fast-forward and mandatory markings after that occur
making the access pattern quite similar to the former fastpath
"special case".

DSACKs are special case that must always be walked.

The local to recv_sack_cache copying could be more intelligent
w.r.t DSACKs which are likely to be there only once but that
is left to a separate patch.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:07 -08:00
Ilpo Järvinen
fd6dad616d [TCP]: Earlier SACK block verification & simplify access to them
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:07 -08:00
Ilpo Järvinen
9e10c47cb9 [TCP]: Create tcp_sacktag_one().
Worker function that implements the main logic of
the inner-most loop of tcp_sacktag_write_queue().

Idea was originally presented by David S. Miller.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:06 -08:00
Ilpo Järvinen
b7d4815f35 [TCP]: Prior_fackets can be replaced by highest_sack seq
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:05 -08:00
Ilpo Järvinen
9f58f3b721 [TCP]: Make lost retrans detection more self-contained
Highest_sack_end_seq is no longer calculated in the loop,
thus it can be pushed to the worker function altogether
making that function independent of the sacktag.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:04 -08:00
Ilpo Järvinen
a47e5a988a [TCP]: Convert highest_sack to sk_buff to allow direct access
It is going to replace the sack fastpath hint quite soon... :-)

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:03 -08:00
Ilpo Järvinen
85cc391c0e [TCP]: non-FACK SACK follows conservative SACK loss recovery
Many assumptions that are true when no reordering or other
strange events happen are not a part of the RFC3517. FACK
implementation is based on such assumptions. Previously (before
the rewrite) the non-FACK SACK was basically doing fast rexmit
and then it times out all skbs when first cumulative ACK arrives,
which cannot really be called SACK based recovery :-).

RFC3517 SACK disables these things:
- Per SKB timeouts & head timeout entry to recovery
- Marking at least one skb while in recovery (RFC3517 does this
  only for the fast retransmission but not for the other skbs
  when cumulative ACKs arrive in the recovery)
- Sacktag's loss detection flavors B and C (see comment before
  tcp_sacktag_write_queue)

This does not implement the "last resort" rule 3 of NextSeg, which
allows retransmissions also when not enough SACK blocks have yet
arrived above a segment for IsLost to return true [RFC3517].

The implementation differs from RFC3517 in these points:
- Rate-halving is used instead of FlightSize / 2
- Instead of using dupACKs to trigger the recovery, the number
  of SACK blocks is used as FACK does with SACK blocks+holes
  (which provides more accurate number). It seems that the
  difference can affect negatively only if the receiver does not
  generate SACK blocks at all even though it claimed to be
  SACK-capable.
- Dupthresh is not a constant one. Dynamical adjustments include
  both holes and sacked segments (equal to what FACK has) due to
  complexity involved in determining the number sacked blocks
  between highest_sack and the reordered segment. Thus it's will
  be an over-estimate.

Implementation note:

tcp_clean_rtx_queue doesn't need a lost_cnt tweak because head
skb at that point cannot be SACKED_ACKED (nor would such
situation last for long enough to cause problems).

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:03 -08:00
Ilpo Järvinen
f577111302 [TCP]: Extend reordering detection to cover CA_Loss partially
This implements more accurately what is stated in sacktag's
overall comment:

  "Both of these heuristics are not used in Loss state, when
   we cannot account for retransmits accurately."

When CA_Loss state is entered, the state changer ensures that
undo_marker is only set if no TCPCB_RETRANS skbs were found,
thus having non-zero undo_marker in CA_Loss basically tells
that the R-bits still accurately reflect the current state
of TCP.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:02 -08:00
Ilpo Järvinen
b9d86585dc [TCP]: Move !in_sack test earlier in sacktag & reorganize if()s
All intermediate conditions include it already, make them
simpler as well.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:01 -08:00
Pavel Emelyanov
c0ef877b2c [NET]: Move sock_valbool_flag to socket.c
The sock_valbool_flag() helper is used in setsockopt to
set or reset some flag on the sock. This helper is required
in the net/socket.c only, so move it there.

Besides, patch two places in sys_setsockopt() that repeat
this helper functionality manually.

Since this is not a bugfix, but a trivial cleanup, I
prepared this patch against net-2.6.25, but it also
applies (with a single offset) to the latest net-2.6.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:54:00 -08:00