linux.git/net/ipv4/ipvs/ip_vs_ctl.c, branch v2.6.25

[NETNS]: Add netns parameter to inet_(dev_)add_type.

2008-01-28T23:01:27+00:00

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: Benjamin Thery 
Acked-by: Daniel Lezcano 
Signed-off-by: Eric W. Biederman 
Signed-off-by: David S. Miller

[IPVS]: Switch to using ctl_paths.

2008-01-28T23:01:08+00:00

The feature of ipvs ctls is that the net/ipv4/vs path
is common for core ipvs ctls and for two schedulers,
so I make it exported and re-use it in modules.

Two other .c files required linux/sysctl.h to make the
extern declaration of this path compile well.

Signed-off-by: Pavel Emelyanov 
Acked-by: Simon Horman 
Signed-off-by: David S. Miller

[IPVS]: Move remaining sysctl handlers over to CTL_UNNUMBERED

2007-11-20T05:51:13+00:00

Switch the remaining IPVS sysctl entries over to to use CTL_UNNUMBERED,
I stronly doubt that anyone is using the sys_sysctl interface to
these variables.

Signed-off-by: Simon Horman 
Signed-off-by: David S. Miller

[IPVS]: Fix sysctl warnings about missing strategy

2007-11-20T05:49:25+00:00

Running the latest git code I get the following messages during boot:
sysctl table check failed: /net/ipv4/vs/drop_entry .3.5.21.4 Missing strategy
[...]		  
sysctl table check failed: /net/ipv4/vs/drop_packet .3.5.21.5 Missing strategy
[...]
sysctl table check failed: /net/ipv4/vs/secure_tcp .3.5.21.6 Missing strategy
[...]
sysctl table check failed: /net/ipv4/vs/sync_threshold .3.5.21.24 Missing strategy

I removed the binary sysctl handler for those messages and also removed
the definitions in ip_vs.h. The alternative would be to implement a 
proper strategy handler, but syscall sysctl is deprecated.

There are other sysctl definitions that are commented out or work with 
the default sysctl_data strategy. I did not touch these. 

Signed-off-by: Christian Borntraeger 
Acked-by: Simon Horman 
Signed-off-by: David S. Miller

[IPVS]: Remove unused exports.

2007-11-13T05:25:24+00:00

This patch removes the following unused EXPORT_SYMBOL's:
- ip_vs_try_bind_dest
- ip_vs_find_dest

Signed-off-by: Adrian Bunk 
Signed-off-by: David S. Miller

[IPVS]: Bind connections on stanby if the destination exists

2007-11-07T12:15:09+00:00

This patch fixes the problem with node overload on director fail-over.
Given the scenario: 2 nodes each accepting 3 connections at a time and 2
directors, director failover occurs when the nodes are fully loaded (6
connections to the cluster) in this case the new director will assign
another 6 connections to the cluster, If the same real servers exist
there.

The problem turned to be in not binding the inherited connections to
the real servers (destinations) on the backup director. Therefore:
"ipvsadm -l" reports 0 connections:
root@test2:~# ipvsadm -l
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  test2.local:5999 wlc
  -> node473.local:5999           Route   1000   0          0
  -> node484.local:5999           Route   1000   0          0

while "ipvs -lnc" is right
root@test2:~# ipvsadm -lnc
IPVS connection entries
pro expire state       source             virtual            destination
TCP 14:56  ESTABLISHED 192.168.0.10:39164 192.168.0.222:5999
192.168.0.51:5999
TCP 14:59  ESTABLISHED 192.168.0.10:39165 192.168.0.222:5999
192.168.0.52:5999

So the patch I am sending fixes the problem by binding the received
connections to the appropriate service on the backup director, if it
exists, else the connection will be handled the old way. So if the
master and the backup directors are synchronized in terms of real
services there will be no problem with server over-committing since
new connections will not be created on the nonexistent real services
on the backup. However if the service is created later on the backup,
the binding will be performed when the next connection update is
received. With this patch the inherited connections will show as
inactive on the backup:

root@test2:~# ipvsadm -l
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  test2.local:5999 wlc
  -> node473.local:5999           Route   1000   0          1
  -> node484.local:5999           Route   1000   0          1

rumen@test2:~$ cat /proc/net/ip_vs
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP  C0A800DE:176F wlc
  -> C0A80033:176F      Route   1000   0          1
  -> C0A80032:176F      Route   1000   0          1

Regards,
Rumen Bogdanovski

Acked-by: Julian Anastasov 
Signed-off-by: Rumen G. Bogdanovski 
Signed-off-by: Simon Horman

[NET]: Make core networking code use seq_open_private

2007-10-10T23:55:33+00:00

This concerns the ipv4 and ipv6 code mostly, but also the netlink
and unix sockets.

The netlink code is an example of how to use the __seq_open_private()
call - it saves the net namespace on this private.

Signed-off-by: Pavel Emelyanov 
Signed-off-by: David S. Miller

[NET]: Make /proc/net per network namespace

2007-10-10T23:49:06+00:00

This patch makes /proc/net per network namespace.  It modifies the global
variables proc_net and proc_net_stat to be per network namespace.
The proc_net file helpers are modified to take a network namespace argument,
and all of their callers are fixed to pass &init_net for that argument.
This ensures that all of the /proc/net files are only visible and
usable in the initial network namespace until the code behind them
has been updated to be handle multiple network namespaces.

Making /proc/net per namespace is necessary as at least some files
in /proc/net depend upon the set of network devices which is per
network namespace, and even more files in /proc/net have contents
that are relevant to a single network namespace.

Signed-off-by: Eric W. Biederman 
Signed-off-by: David S. Miller

[NETFILTER]: Fix/improve deadlock condition on module removal netfilter

2007-09-11T09:28:26+00:00

So I've had a deadlock reported to me.  I've found that the sequence of
events goes like this:

1) process A (modprobe) runs to remove ip_tables.ko

2) process B (iptables-restore) runs and calls setsockopt on a netfilter socket,
increasing the ip_tables socket_ops use count

3) process A acquires a file lock on the file ip_tables.ko, calls remove_module
in the kernel, which in turn executes the ip_tables module cleanup routine,
which calls nf_unregister_sockopt

4) nf_unregister_sockopt, seeing that the use count is non-zero, puts the
calling process into uninterruptible sleep, expecting the process using the
socket option code to wake it up when it exits the kernel

4) the user of the socket option code (process B) in do_ipt_get_ctl, calls
ipt_find_table_lock, which in this case calls request_module to load
ip_tables_nat.ko

5) request_module forks a copy of modprobe (process C) to load the module and
blocks until modprobe exits.

6) Process C. forked by request_module process the dependencies of
ip_tables_nat.ko, of which ip_tables.ko is one.

7) Process C attempts to lock the request module and all its dependencies, it
blocks when it attempts to lock ip_tables.ko (which was previously locked in
step 3)

Theres not really any great permanent solution to this that I can see, but I've
developed a two part solution that corrects the problem

Part 1) Modifies the nf_sockopt registration code so that, instead of using a
use counter internal to the nf_sockopt_ops structure, we instead use a pointer
to the registering modules owner to do module reference counting when nf_sockopt
calls a modules set/get routine.  This prevents the deadlock by preventing set 4
from happening.

Part 2) Enhances the modprobe utilty so that by default it preforms non-blocking
remove operations (the same way rmmod does), and add an option to explicity
request blocking operation.  So if you select blocking operation in modprobe you
can still cause the above deadlock, but only if you explicity try (and since
root can do any old stupid thing it would like....  :)  ).

Signed-off-by: Neil Horman 
Signed-off-by: Patrick McHardy 
Signed-off-by: David S. Miller

[IPVS]: Use IP_VS_WAIT_WHILE when encessary.

2007-08-14T05:52:15+00:00

For architectures that don't have a volatile atomic_ts constructs like
while (atomic_read(&something)); might result in endless loops since a
barrier() is missing which forces the compiler to generate code that
actually reads memory contents.
Fix this in ipvs by using the IP_VS_WAIT_WHILE macro which resolves to
while (expr) { cpu_relax(); }
(why isn't this open coded btw?)

Signed-off-by: Heiko Carstens 
Signed-off-by: Simon Horman 
Signed-off-by: David S. Miller