Commit Graph

241 Commits

Author SHA1 Message Date
John Heffner 0e57976b63 [TCP]: Add Scalable TCP congestion control module.
This patch implements Tom Kelly's Scalable TCP congestion control algorithm 
for the modular framework.

The algorithm has some nice scaling properties, and has been used a fair bit 
in research, though is known to have significant fairness issues, so it's not 
really suitable for general purpose use.

Signed-off-by: John Heffner <jheffner@psc.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 12:29:07 -07:00
Baruch Even a7868ea68d [TCP]: Add H-TCP congestion control module.
H-TCP is a congestion control algorithm developed at the Hamilton Institute, by
Douglas Leith and Robert Shorten. It is extending the standard Reno algorithm
with mode switching is thus a relatively simple modification.

H-TCP is defined in a layered manner as it is still a research platform. The
basic form includes the modification of beta according to the ratio of maxRTT
to min RTT and the alpha=2*factor*(1-beta) relation, where factor is dependant
on the time since last congestion.

The other layers improve convergence by adding appropriate factors to alpha.

The following patch implements the H-TCP algorithm in it's basic form.

Signed-Off-By: Baruch Even <baruch@ev-en.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 12:28:11 -07:00
Stephen Hemminger b87d8561d8 [TCP]: Add TCP Vegas congestion control module.
TCP Vegas code modified for the new TCP infrastructure.  
Vegas now uses microsecond resolution timestamps for 
better estimation of performance over higher speed links.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 12:27:19 -07:00
Daniele Lacamera 835b3f0c0d [TCP]: Add TCP Hybla congestion control module.
TCP Hybla congestion avoidance.

- "In heterogeneous networks, TCP connections that incorporate a
terrestrial or satellite radio link are greatly disadvantaged with
respect to entirely wired connections, because of their longer round
trip times (RTTs). To cope with this problem, a new TCP proposal, the
TCP Hybla, is presented and discussed in the paper[1]. It stems from an
analytical evaluation of the congestion window dynamics in the TCP
standard versions (Tahoe, Reno, NewReno), which suggests the necessary
modifications to remove the performance dependence on RTT.[...]"[1]

[1]: Carlo Caini, Rosario Firrincieli, "TCP Hybla: a TCP enhancement for
heterogeneous networks",
International Journal of Satellite Communications and Networking
Volume 22, Issue 5 , Pages 547 - 566. September 2004.

Signed-off-by: Daniele Lacamera (root at danielinux.net)net
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 12:26:34 -07:00
John Heffner a628d29b56 [TCP]: Add High Speed TCP congestion control module.
Sally Floyd's high speed TCP congestion control.
This is useful for comparison and research.

Signed-off-by: John Heffner <jheffner@psc.edu>
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 12:24:58 -07:00
Stephen Hemminger 8727076289 [TCP]: Add TCP Westwood congestion control module.
This is the existing 2.6.12 Westwood code moved from tcp_input
to the new congestion framework. A lot of the inline functions
have been eliminated to try and make it clearer.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 12:24:09 -07:00
Stephen Hemminger 83803034f4 [TCP]: Add TCP BIC congestion control module.
TCP BIC congestion control reworked to use the new congestion control 
infrastructure. This version is more up to date than the BIC
code in 2.6.12; it incorporates enhancements from BICTCP 1.1, 
to handle low latency links.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 12:23:25 -07:00
Stephen Hemminger 056ede6cfa [TCP]: Report congestion control algorithm in tcp_diag.
Enhancement to the tcp_diag interface used by the iproute2 ss command
to report the tcp congestion control being used by a socket.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 12:21:28 -07:00
Stephen Hemminger 7c99c909fa [TCP]: Change tcp_diag to use the existing __RTA_PUT() macro.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 12:20:36 -07:00
Stephen Hemminger 317a76f9a4 [TCP]: Add pluggable congestion control algorithm infrastructure.
Allow TCP to have multiple pluggable congestion control algorithms.
Algorithms are defined by a set of operations and can be built in
or modules.  The legacy "new RENO" algorithm is used as a starting
point and fallback.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 12:19:55 -07:00
Paulo Marques 543537bd92 [PATCH] create a kstrdup library function
This patch creates a new kstrdup library function and changes the "local"
implementations in several places to use this function.

Most of the changes come from the sound and net subsystems.  The sound part
had already been acknowledged by Takashi Iwai and the net part by David S.
Miller.

I left UML alone for now because I would need more time to read the code
carefully before making changes there.

Signed-off-by: Paulo Marques <pmarques@grupopie.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 09:45:18 -07:00
Linus Torvalds 060de20e82 Merge rsync://rsync.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2005-06-22 23:11:50 -07:00
Shaun Pereira ebc3f64b86 [X25]: Fast select with no restriction on response
This patch is a follow up to patch 1 regarding "Selective Sub Address
matching with call user data".  It allows use of the Fast-Select-Acceptance
optional user facility for X.25.

This patch just implements fast select with no restriction on response
(NRR).  What this means (according to ITU-T Recomendation 10/96 section
6.16) is that if in an incoming call packet, the relevant facility bits are
set for fast-select-NRR, then the called DTE can issue a direct response to
the incoming packet using a call-accepted packet that contains
call-user-data.  This patch allows such a response.  

The called DTE can also respond with a clear-request packet that contains
call-user-data.  However, this feature is currently not implemented by the
patch.

How is Fast Select Acceptance used?
By default, the system does not allow fast select acceptance (as before).
To enable a response to fast select acceptance,  
After a listen socket in created and bound as follows
	socket(AF_X25, SOCK_SEQPACKET, 0);
	bind(call_soc, (struct sockaddr *)&locl_addr, sizeof(locl_addr));
but before a listen system call is made, the following ioctl should be used.
	ioctl(call_soc,SIOCX25CALLACCPTAPPRV);
Now the listen system call can be made
	listen(call_soc, 4);
After this, an incoming-call packet will be accepted, but no call-accepted 
packet will be sent back until the following system call is made on the socket
that accepts the call
	ioctl(vc_soc,SIOCX25SENDCALLACCPT);
The network (or cisco xot router used for testing here) will allow the 
application server's call-user-data in the call-accepted packet, 
provided the call-request was made with Fast-select NRR.

Signed-off-by: Shaun Pereira <spereira@tusc.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-22 22:16:17 -07:00
Shaun Pereira cb65d506c3 [X25]: Selective sub-address matching with call user data.
From: Shaun Pereira <spereira@tusc.com.au>

This is the first (independent of the second) patch of two that I am
working on with x25 on linux (tested with xot on a cisco router).  Details
are as follows.

Current state of module:

A server using the current implementation (2.6.11.7) of the x25 module will
accept a call request/ incoming call packet at the listening x.25 address,
from all callers to that address, as long as NO call user data is present
in the packet header.

If the server needs to choose to accept a particular call request/ incoming
call packet arriving at its listening x25 address, then the kernel has to
allow a match of call user data present in the call request packet with its
own.  This is required when multiple servers listen at the same x25 address
and device interface.  The kernel currently matches ALL call user data, if
present.

Current Changes:

This patch is a follow up to the patch submitted previously by Andrew
Hendry, and allows the user to selectively control the number of octets of
call user data in the call request packet, that the kernel will match.  By
default no call user data is matched, even if call user data is present. 
To allow call user data matching, a cudmatchlength > 0 has to be passed
into the kernel after which the passed number of octets will be matched. 
Otherwise the kernel behavior is exactly as the original implementation.

This patch also ensures that as is normally the case, no call user data
will be present in the Call accepted / call connected packet sent back to
the caller 

Future Changes on next patch:

There are cases however when call user data may be present in the call
accepted packet.  According to the X.25 recommendation (ITU-T 10/96)
section 5.2.3.2 call user data may be present in the call accepted packet
provided the fast select facility is used.  My next patch will include this
fast select utility and the ability to send up to 128 octets call user data
in the call accepted packet provided the fast select facility is used.  I
am currently testing this, again with xot on linux and cisco.  

Signed-off-by: Shaun Pereira <spereira@tusc.com.au>

(With a fix from Alexey Dobriyan <adobriyan@gmail.com>)
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-22 22:15:01 -07:00
James Lamanna 68d3187200 [EBTABLES]: vfree() checking cleanups
From: jlamanna@gmail.com

ebtables.c vfree() checking cleanups.

Signed-off by: James Lamanna <jlamanna@gmail.com>
Signed-off-by: Domen Puncer <domen@coderock.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-22 22:12:57 -07:00
Nishanth Aravamudan 285b3afefa [ATALK] aarp: replace schedule_timeout() with msleep()
From: Nishanth Aravamudan <nacc@us.ibm.com>

Use msleep() instead of schedule_timeout() to guarantee the task
delays as expected. The current code is not wrong, but it does not account for
early return due to signals, so I think msleep() should be appropriate.

Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Signed-off-by: Domen Puncer <domen@coderock.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-22 22:11:44 -07:00
Chuck Short 7abaa27c1c [IPV4]: Fix route.c gcc4 warnings
Signed-off by: Chuck Short <zulcss@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-22 22:10:23 -07:00
Jeff Moyer fbeec2e155 [NETPOLL]: allow multiple netpoll_clients to register against one interface
This patch provides support for registering multiple netpoll clients to the
same network device.  Only one of these clients may register an rx_hook,
however.  In practice, this restriction has not been problematic.  It is
worth mentioning, though, that the current design can be easily extended to
allow for the registration of multiple rx_hooks.

The basic idea of the patch is that the rx_np pointer in the netpoll_info
structure points to the struct netpoll that has rx_hook filled in.  Aside
from this one case, there is no need for a pointer from the struct
net_device to an individual struct netpoll.

A lock is introduced to protect the setting and clearing of the np_rx
pointer.  The pointer will only be cleared upon netpoll client module
removal, and the lock should be uncontested.

Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-22 22:05:59 -07:00
Jeff Moyer 115c1d6e61 [NETPOLL]: Introduce a netpoll_info struct
This patch introduces a netpoll_info structure, which the struct net_device
will now point to instead of pointing to a struct netpoll.  The reason for
this is two-fold: 1) fields such as the rx_flags, poll_owner, and poll_lock
should be maintained per net_device, not per netpoll;  and 2) this is a first
step in providing support for multiple netpoll clients to register against the
same net_device.

The struct netpoll is now pointed to by the netpoll_info structure.  As
such, the previous behaviour of the code is preserved.

Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-22 22:05:31 -07:00
Eric Dumazet f31f5f0512 [NET]: dont use strlen() but the result from a prior sprintf()
Small patch to save an unecessary call to strlen() : sprintf() gave us
the length, just trust it.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-22 14:32:51 -07:00
Chuck Lever ae3884621b [PATCH] RPC: kick off socket connect operations faster
Make the socket transport kick the event queue to start socket connects
 immediately.  This should improve responsiveness of applications that are
 sensitive to slow mount operations (like automounters).

 We are now also careful to cancel the connect worker before destroying
 the xprt.  This eliminates a race where xprt_destroy can finish before
 the connect worker is even allowed to run.

 Test-plan:
 Destructive testing (unplugging the network temporarily).  Connectathon
 with UDP and TCP.  Hard-code impossibly small connect timeout.

 Version: Fri, 29 Apr 2005 15:32:01 -0400

 Signed-off-by: Chuck Lever <cel@netapp.com>
 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2005-06-22 16:07:32 -04:00
Chuck Lever 20e5ac828d [PATCH] RPC: TCP reconnects are too slow
When the network layer reports a connection close, the RPC task
 waiting to reconnect should be notified so it can retry immediately
 instead of waiting for the normal connection establishment timeout.

 This reverts a change made in 2.6.6 as part of adding client support
 for RPC over TCP socket idle timeouts.

 Test-plan:
 Destructive testing with NFS over TCP mounts.

 Version: Fri, 29 Apr 2005 15:31:46 -0400

 Signed-off-by: Chuck Lever <cel@netapp.com>
 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2005-06-22 16:07:32 -04:00
Trond Myklebust 0f9dc2b168 [PATCH] RPC: Clean up socket autodisconnect
Cancel autodisconnect requests inside xprt_transmit() in order to avoid
 races.
 Use more efficient del_singleshot_timer_sync()

 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2005-06-22 16:07:31 -04:00
Trond Myklebust 14b218a8e4 [PATCH] RPC: Ensure rpc calls respects the RPC_NOINTR flag
For internal purposes, the rpc_clnt_sigmask() call is replaced by
 a call to rpc_task_sigmask(), which ensures that the current task
 sigmask respects both the client cl_intr flag and the per-task NOINTR flag.

 Problem noted by Jiaying Zhang.

 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2005-06-22 16:07:30 -04:00
Andreas Gruenbacher 9ba02638e4 [PATCH] RPC: Allow the sunrpc server to multiplex serveral programs on a single port
The NFS and NFSACL programs run on the same RPC transport.  This patch adds
 support for this by converting svc_program into a chained list of programs
 (server-side).

 Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
 Signed-off-by: Olaf Kirch <okir@suse.de>
 Signed-off-by: Andrew Morton <akpm@osdl.org>
 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2005-06-22 16:07:22 -04:00
Andreas Gruenbacher bd8100e7ed [PATCH] RPC: Encode and decode arbitrary XDR arrays
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
 Acked-by: Olaf Kirch <okir@suse.de>
 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2005-06-22 16:07:20 -04:00
Trond Myklebust 7e06b53d79 [PATCH] RPC: fix accounting bug in the case of a truncated RPC message
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2005-06-22 16:07:19 -04:00
Olaf Kirch e053d1ab62 [PATCH] RPC: Lazy RPC receive buffer allocation
Signed-off-by: Olaf Kirch <okir@suse.de>
 Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2005-06-22 16:07:19 -04:00
Andreas Gruenbacher 007e251f2b [PATCH] RPC: Allow multiple RPC client programs to share the same transport
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
 Acked-by: Olaf Kirch <okir@suse.de>
 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2005-06-22 16:07:18 -04:00
Andreas Gruenbacher cdf477068e [PATCH] RPC: Return -EPFNOSUPPORT for RPC programs that are unavailable
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
 Signed-off-by: Olaf Kirch <okir@suse.de>
 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2005-06-22 16:07:17 -04:00
J. Bruce Fields 6a19275ada [PATCH] RPC: [PATCH] improve rpcauthauth_create error returns
Currently we return -ENOMEM for every single failure to create a new auth.
 This is actually accurate for auth_null and auth_unix, but for auth_gss it's a
 bit confusing.

 Allow rpcauth_create (and the ->create methods) to return errors.  With this
 patch, the user may sometimes see an EINVAL instead.  Whee.

 Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2005-06-22 16:07:16 -04:00
J. Bruce Fields 438b6fdebf [PATCH] RPC: Don't fall back from krb5p to krb5i
We shouldn't be silently falling back from krb5p to krb5i.

 Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2005-06-22 16:07:16 -04:00
Trond Myklebust 96651ab341 [PATCH] RPC: Shrink struct rpc_task by switching to wait_on_bit()
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2005-06-22 16:07:07 -04:00
Trond Myklebust 5ee0ed7d3a [PATCH] RPC: Make rpc_create_client() probe server for RPC program+version support
Ensure that we don't create an RPC client without checking that the server
 does indeed support the RPC program + version that we are trying to set up.

 This enables us to immediately return an error to "mount" if it turns out
 that the server is only supporting NFSv2, when we requested NFSv3 or NFSv4.

 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2005-06-22 16:07:04 -04:00
Trond Myklebust 5b616f5d59 [PATCH] RPC: Make rpc_create_client() destroy the transport on failure.
This saves us a couple of lines of cleanup code for each call.

 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2005-06-22 16:07:03 -04:00
Trond Myklebust 334ccfd545 [PATCH] RPC: Ensure XDR iovec length is initialized correctly in call_header
Fix up call_header() so that it calls xdr_adjust_iovec().
 Fix calculation of the scratch buffer length in xdr_init_encode().

 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2005-06-22 16:07:02 -04:00
Trond Myklebust d05fdb0cec [PATCH] RPC: Fix a race with rpc_restart_call()
If the task->tk_exit() wants to restart the RPC call after delaying
 then the current RPC code will clobber the timer by calling
 rpc_delete_timer() immediately after re-entering the loop in
 __rpc_execute().

 Problem noticed by Oleg Nesterov <oleg@tv-sign.ru>
 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2005-06-22 16:07:01 -04:00
Harald Welte 5d927eb010 [NETFILTER]: Fix handling of ICMP packets (RELATED) in ipt_CLUSTERIP target.
Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-22 12:37:50 -07:00
Kumar Gala b535420739 [PATCH] Fix extra double quote in IPV4 Kconfig
Kconfig option had an extra double quote at the end of the line
which was causing in warning when building.

Signed-off-by: Kumar Gala <kumar.gala@freescale.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-22 10:40:39 -07:00
David S. Miller 90f66914c8 [IPV4]: Fix fib_trie.c's args to fib_dump_info().
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-21 14:43:28 -07:00
Patrick McHardy 047601bf7c [NETFILTER]: Fix ip6t_LOG sit tunnel logging
Sit tunnel logging is currently broken:

MAC=01:23:45:67:89:ab->01:23:45:47:89:ac TUNNEL=123.123.  0.123-> 12.123.  6.123

Apart from the broken IP address, MAC addresses are printed differently
for sit tunnels than for everything else.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-21 14:07:13 -07:00
Patrick McHardy 2715bcf9ef [NETFILTER]: Drop conntrack reference in ip_call_ra_chain()/ip_mr_input()
Drop reference before handing the packets to raw_rcv()

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-21 14:06:24 -07:00
Patrick McHardy 6150bacfec [NETFILTER]: Check TCP checksum in ipt_REJECT
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-21 14:03:46 -07:00
Keir Fraser e3be8ba792 [NETFILTER]: Avoid unncessary checksum validation in UDP connection tracking
Signed-off-by: Keir Fraser <Keir.Fraser@xl.cam.ac.uk>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-21 14:03:23 -07:00
Patrick McHardy 97216c799a [NETFILTER]: Missing owner-field initialization in ip6table_raw
I missed this one when fixing up iptable_raw.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-21 14:03:01 -07:00
Phil Oester 1d3cdb41f5 [NETFILTER]: expectation timeouts are compulsory
Since expectation timeouts were made compulsory [1], there is no need to
check for them in ip_conntrack_expect_insert.

[1] https://lists.netfilter.org/pipermail/netfilter-devel/2005-January/018143.html

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>
2005-06-21 14:02:42 -07:00
Patrick McHardy e98231858b [NETFILTER]: Restore netfilter assumptions in IPv6 multicast
Netfilter assumes that skb->data == skb->nh.ipv6h

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-21 14:02:15 -07:00
Patrick McHardy 18b8afc771 [NETFILTER]: Kill nf_debug
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-21 14:01:57 -07:00
Patrick McHardy e45b1be8bc [NETFILTER]: Kill lockhelp.h
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-21 14:01:30 -07:00
David L Stevens c9e3e8b695 [IPV6]: multicast join and misc
Here is a simplified version of the patch to fix a bug in IPv6
multicasting. It:

1) adds existence check & EADDRINUSE error for regular joins
2) adds an exception for EADDRINUSE in the source-specific multicast
        join (where a prior join is ok)
3) adds a missing/needed read_lock on sock_mc_list; would've raced
        with destroying the socket on interface down without
4) adds a "leave group" in the (INCLUDE, empty) source filter case.
        This frees unneeded socket buffer memory, but also prevents
        an inappropriate interaction among the 8 socket options that
        mess with this. Some would fail as if in the group when you
        aren't really.

Item #4 had a locking bug in the last version of this patch; rather than
removing the idev->lock read lock only, I've simplified it to remove
all lock state in the path and treat it as a direct "leave group" call for
the (INCLUDE,empty) case it covers. Tested on an MP machine. :-)

Much thanks to HoerdtMickael <hoerdt@clarinet.u-strasbg.fr> who
reported the original bug.

Signed-off-by: David L Stevens <dlstevens@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-21 13:58:25 -07:00