There are options, which are set up on a socket while performing
TCP handshake. Need to resurrect them on a socket while repairing.
A new sockoption accepts a buffer and parses it. The buffer should
be CODE:VALUE sequence of bytes, where CODE is standard option
code and VALUE is the respective value.

Only 4 options should be handled on repaired socket.

To read 3 out of 4 of these options the TCP_INFO sockoption can be
used. An ability to get the last one (the mss_clamp) was added by
the previous patch.

Now the restore. Three of these options -- timestamp_ok, mss_clamp
and snd_wscale -- are just restored on a coket.

The sack_ok flags has 2 issues. First, whether or not to do sacks
at all. This flag is just read and set back. No other sack  info is
saved or restored, since according to the standart and the code
dropping all sack-ed segments is OK, the sender will resubmit them
again, so after the repair we will probably experience a pause in
connection. Next, the fack bit. It's just set back on a socket if
the respective sysctl is set. No collected stats about packets flow
is preserved. As far as I see (plz, correct me if I'm wrong) the
fack-based congestion algorithm survives dropping all of the stats
and repairs itself eventually, probably losing the performance for
that period.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The mss_clamp is the only connection-time negotiated option which
cannot be obtained from the user space. Make the TCP_MAXSEG sockopt
report one in the repair mode.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Reading queues under repair mode is done with recvmsg call.
The queue-under-repair set by TCP_REPAIR_QUEUE option is used
to determine which queue should be read. Thus both send and
receive queue can be read with this.

Caller must pass the MSG_PEEK flag.

Writing to queues is done with sendmsg call and yet again --
the repair-queue option can be used to push data into the
receive queue.

When putting an skb into receive queue a zero tcp header is
appented to its head to address the tcp_hdr(skb)->syn and
the ->fin checks by the (after repair) tcp_recvmsg. These
flags flags are both set to zero and that's why.

The fin cannot be met in the queue while reading the source
socket, since the repair only works for closed/established
sockets and queueing fin packet always changes its state.

The syn in the queue denotes that the respective skb's seq
is "off-by-one" as compared to the actual payload lenght. Thus,
at the rcv queue refill we can just drop this flag and set the
skb's sequences to precice values.

When the repair mode is turned off, the write queue seqs are
updated so that the whole queue is considered to be 'already sent,
waiting for ACKs' (write_seq = snd_nxt <= snd_una). From the
protocol POV the send queue looks like it was sent, but the data
between the write_seq and snd_nxt is lost in the network.

This helps to avoid another sockoption for setting the snd_nxt
sequence. Leaving the whole queue in a 'not yet sent' state (as
it will be after sendmsg-s) will not allow to receive any acks
from the peer since the ack_seq will be after the snd_nxt. Thus
even the ack for the window probe will be dropped and the
connection will be 'locked' with the zero peer window.
Signed-off-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This includes (according the the previous description):

* TCP_REPAIR sockoption

This one just puts the socket in/out of the repair mode.
Allowed for CAP_NET_ADMIN and for closed/establised sockets only.
When repair mode is turned off and the socket happens to be in
the established state the window probe is sent to the peer to
'unlock' the connection.

* TCP_REPAIR_QUEUE sockoption

This one sets the queue which we're about to repair. The
'no-queue' is set by default.

* TCP_QUEUE_SEQ socoption

Sets the write_seq/rcv_nxt of a selected repaired queue.
Allowed for TCP_CLOSE-d sockets only. When the socket changes
its state the other seq-s are changed by the kernel according
to the protocol rules (most of the existing code is actually
reused).

* Ability to forcibly bind a socket to a port

The sk->sk_reuse is set to SK_FORCE_REUSE.

* Immediate connect modification

The connect syscall initializes the connection, then directly jumps
to the code which finalizes it.

* Silent close modification

The close just aborts the connection (similar to SO_LINGER with 0
time) but without sending any FIN/RST-s to peer.
Signed-off-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is just the preparation patch, which makes the needed for
TCP repair code ready for use.
Signed-off-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Name them in a "backward compatible" manner, i.e. reuse or not
are still 1 and 0 respectively. The reuse value of 2 means that
the socket with it will forcibly reuse everyone else's port.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The two options are separate, and some platforms (e.g. arm pxa)
have ISA slots but no ISA dma controller, so they cannot build
drivers using the DMA API functions.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some architectures like ARM cannot handle large numbers as
arguments to udelay, so the drivers should use mdelay when
delaying for multiple miliseconds.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

No driver should spin the CPU for 10ms, so better use
an msleep, which is allowed in the ->suspend function.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The ax88796 driver uses the CRC32 functions, so make sure that
they are actually enabled.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The iwmc3200 driver selects other code in Kconfig that depends on
EXPERIMENTAL. Kconfig warns about this when CONFIG_EXPERIMENTAL
is not already set, so logically, these options should also
be marked experimental or promoted to stable.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The caif_shmcore requires io.h in order to use ioremap, so include that
explicitly to compile in all configurations.

Also add a note about the use of ioremap(), which is not a proper way
to map a DMA buffer into kernel space. It's not completely clear what
the intention is for using ioremap, but it is clear that the result
of ioremap must not simply be accessed using kernel pointers but
should use readl/writel or memcopy_{to,from}io. Assigning the result
of ioremap to a regular pointer that can also be set to something
else is not ok.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Drivers that refer to a __devexit function in an operations
structure need to annotate that pointer with __devexit_p so
replace it with a NULL pointer when the section gets discarded.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The davinci_emac driver can be a module, so the symbols
it needs from the cpdma driver must be exported.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The time stamping code in this driver appears to have been copied from
the ixp4xx_eth.c driver, including this timing comment. I had actually
measured the time stamp delay on an IXP425, but I really doubt that this
value also applies here.
Signed-off-by: NRichard Cochran <richardcochran@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fixes code which needlessly ran the BPF twice per
packet. Instead, we just run the classifier once and test
whether the packet is any kind of PTP event message.
Signed-off-by: NRichard Cochran <richardcochran@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fixes the driver so that multicast PTP event messages can
be recognized by the hardware time stamping unit. The station address
register must be set according to the desired transport type.

[ RC - Rebased Takahiro's changes and wrote a commit message
  explaining the changes. ]
Signed-off-by: NTakahiro Shimizu <tshimizu818@gmail.com>
Signed-off-by: NRichard Cochran <richardcochran@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We will let the pch_gbe code do that according to the receive time stamp
filter.

[ RC - Rebased Takahiro's changes and wrote a commit message
  explaining the changes. ]
Signed-off-by: NTakahiro Shimizu <tshimizu818@gmail.com>
Signed-off-by: NRichard Cochran <richardcochran@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch clears up a few coding style issues:

- Makes two function definitions a bit nicer looking.
- Remove unneeded parentheses.
- Simplify macros for register bits.

[ RC - Rebased Takahiro's changes and wrote a commit message
  explaining the changes. ]
Signed-off-by: NTakahiro Shimizu <tshimizu818@gmail.com>
Signed-off-by: NRichard Cochran <richardcochran@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The code in phc_gbe_main will need to call this method in order to set the
station address register according to the receive time stamping filter.

[ RC - Rebased Takahiro's changes and wrote a commit message
  explaining the changes. ]
Signed-off-by: NTakahiro Shimizu <tshimizu818@gmail.com>
Signed-off-by: NRichard Cochran <richardcochran@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The reset logic after a Rx FIFO overrun will clear the programmed
multicast addresses. This patch fixes the issue by reprogramming the
registers after the reset.

[ RC - Rebased Takahiro's changes and wrote a commit message
  explaining the changes. ]
Signed-off-by: NTakahiro Shimizu <tshimizu818@gmail.com>
Signed-off-by: NRichard Cochran <richardcochran@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch makes logic surrounding the test of the
transmit time stamping flag more readable.

[ RC - Rebased Takahiro's changes and wrote a commit message
  explaining the changes. ]
Signed-off-by: NTakahiro Shimizu <tshimizu818@gmail.com>
Signed-off-by: NRichard Cochran <richardcochran@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fixes the helper functions that give the transmit and
receive time stamps to return nanoseconds, instead of arbitrary clock
ticks.

[ RC - Rebased Takahiro's changes and wrote a commit message
  explaining the changes. ]
Signed-off-by: NTakahiro Shimizu <tshimizu818@gmail.com>
Signed-off-by: NRichard Cochran <richardcochran@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

All of the users have been converted to use registera_net_sysctl so we
no longer need register_net_sysctl.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We don't use struct ctl_path anymore so delete the exported constants.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This results in code with less boiler plate that is a bit easier
to read.

Additionally stops us from using compatibility code in the sysctl
core, hastening the day when the compatibility code can be removed.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There isn't much advantage here except that strings paths are a bit
easier to read, and converting everything to them allows me to kill off
ctl_path.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Using an ascii path to register_net_sysctl as opposed to the slightly
awkward ctl_path allows for much simpler code.

We no longer need to malloc dev_name to keep it alive the length of our
sysctl register instead we can use a small temporary buffer on the
stack.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Using an ascii path to register_net_sysctl as opposed to the slightly
awkward ctl_path allows for much simpler code.

We no longer need to malloc dev_name to keep it alive the length of our
sysctl register instead we can use a small temporary buffer on the
stack.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Using an ascii path to register_net_sysctl as opposed to the slightly
awkward ctl_path allows for much simpler code.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Using an ascii path to register_net_sysctl as opposed to the slightly
awkward ctl_path allows for much simpler code.

We no longer need to malloc dev_name to keep it alive the length of our
sysctl register instead we can use a small temporary buffer on the
stack.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The sysctl core no longer natively understands sysctl tables
with .child entries.

Split the ipv6_table to remove the .child entries.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The sysctl core no longer natively understands sysctl tables with .child
entries.

Kill the intermediate tables and use register_net_sysctl directly to
remove the need for compatibility code.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Don't register/unregister every ax25 table in a batch.  Instead register
and unregister per device ax25 sysctls as ax25 devices come and go.

This moves ax25 to be a completely modern sysctl user.  Registering the
sysctls in just the initial network namespace, removing the use of
.child entries that are no longer natively supported by the sysctl core
and taking advantage of the fact that there are no longer any ordering
constraints between registering and unregistering different sysctl
tables.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

sysctl no longer requires explicit creation of directories.  The neigh
directory is always populated with at least a default entry so this
won't cause any user visible changes.

Delete the ipv4_path and the ipv4_skeleton these are no longer needed.

Directly register the ipv4_route_table.

And since I am an idiot remove the header definitions that I should
have removed in the previous patch.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

sysctl no longer requires explicit creation of directories.  The neigh
directory is always populated with at least a default entry so this
should cause no user visible changes.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

On the next line we register the net_core_table in net/core which
creates the directory and ensures it exists.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This makes it clearer which sysctls are relative to your current network
namespace.

This makes it a little less error prone by not exposing sysctls for the
initial network namespace in other namespaces.

This is the same way we handle all of our other network interfaces to
userspace and I can't honestly remember why we didn't do this for
sysctls right from the start.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

register_sysctl_rotable never caught on as an interesting way to
register sysctls.  My take on the situation is that what we want are
sysctls that we can only see in the initial network namespace.  What we
have implemented with register_sysctl_rotable are sysctls that we can
see in all of the network namespaces and can only change in the initial
network namespace.

That is a very silly way to go.  Just register the network sysctls
in the initial network namespace and we don't have any weird special
cases to deal with.

The sysctls affected are:
/proc/sys/net/ipv4/ipfrag_secret_interval
/proc/sys/net/ipv4/ipfrag_max_dist
/proc/sys/net/ipv6/ip6frag_secret_interval
/proc/sys/net/ipv6/mld_max_msf

I really don't expect anyone will miss them if they can't read them in a
child user namespace.

CC: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If the netfilter code is modified to use register_net_sysctl_table the
kernel fails to boot because the per net sysctl infrasturce is not setup
soon enough.  So to avoid races call net_sysctl_init from sock_init().
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>