This patch adds functionality for avoiding orphaning SKB too early.
The original skb is stashed away and the original destructor is called
from the hi-jacked flow-on callback. If CAIF interface goes down and a
hi-jacked SKB exists, the original skb->destructor is restored.
Signed-off-by: NSjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Flow control is implemented by inspecting the qdisc queue length
in order to detect potential overflow on the TX queue. When a threshold
is reached flow-off is sent upwards in the CAIF stack. At the same time
the skb->destructor is hi-jacked by orphaning the SKB and the original
destructor is replaced with a "flow-on" callback. When the "hi-jacked"
SKB is consumed the queue should be empty, and the "flow-on" callback
is called and xon is sent upwards in the CAIF stack.
Signed-off-by: NSjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

NCM 1.0 does not support anything but Ethernet framing, hence
CAIF payload will be put into Ethernet frames.

Discovery is based on fixed USB vendor 0x04cc (ST-Ericsson),
product-id 0x230f (NCM). In this variant only CAIF payload is sent over
the NCM interface.

The CAIF stack (cfusbl.c) will when USB interface register first check if
we got a CDC NCM USB interface with the right VID, PID.
It will then read the device's Ethernet address and create a 'template'
Ethernet TX header, using a broadcast address as the destination address,
and EthType 0x88b5 (802.1 Local Experimental - vendor specific).

A protocol handler for 0x88b5 is setup for reception of CAIF frames from
the CDC NCM USB interface.
Signed-off-by: NSjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove unused enum cfcnfg_phy_type and the parameter to cfserl_create.
Signed-off-by: NSjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Enrolling CAIF link layers are refactored.
Signed-off-by: NSjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

With calls to modular infrastructure, these files really
needs the full module.h header.  Call it out so some of the
cleanups of implicit and unrequired includes elsewhere can be
cleaned up.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

The caif code will register its own pernet_operations, and then register
a netdevice_notifier. Each time the netdevice_notifier is triggered,
it'll do some stuff... including a lookup of its own pernet stuff with
net_generic().

If the net_generic() call ever returns NULL, the caif code will BUG().
That doesn't seem *so* unreasonable, I suppose — it does seem like it
should never happen.

However, it *does* happen. When we clone a network namespace,
setup_net() runs through all the pernet_operations one at a time. It
gets to loopback before it gets to caif. And loopback_net_init()
registers a netdevice... while caif hasn't been initialised. So the caif
netdevice notifier triggers, and immediately goes BUG().

We could imagine a complex and overengineered solution to this generic
class of problems, but this patch takes the simple approach. It just
makes caif_device_notify() *not* go looking for its pernet data
structures if the device it's being notified about isn't a caif device
in the first place.

Cc: stable@kernel.org
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>
Acked-by: NSjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit bd30ce4b (caif: Use RCU instead of spin-lock in caif_dev.c)
added a potential NULL dereference in case alloc_percpu() fails.

caif_device_alloc() can also use GFP_KERNEL instead of GFP_ATOMIC.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
CC: Sjur Brændeland <sjur.brandeland@stericsson.com>
Acked-by: NSjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It was suggested by "make versioncheck" that the follwing includes of
linux/version.h are redundant:

  /home/jj/src/linux-2.6/net/caif/caif_dev.c: 14 linux/version.h not needed.
  /home/jj/src/linux-2.6/net/caif/chnl_net.c: 10 linux/version.h not needed.
  /home/jj/src/linux-2.6/net/ipv4/gre.c: 19 linux/version.h not needed.
  /home/jj/src/linux-2.6/net/netfilter/ipset/ip_set_core.c: 20 linux/version.h not needed.
  /home/jj/src/linux-2.6/net/netfilter/xt_set.c: 16 linux/version.h not needed.

and it seems that it is right.

Beyond manually inspecting the source files I also did a few build
tests with various configs to confirm that including the header in
those files is indeed not needed.

Here's a patch to remove the pointless includes.
Signed-off-by: NJesper Juhl <jj@chaosbits.net>
Acked-by: NJozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In case of checksum error, the framing layer returns -EILSEQ, but
does not free the packet. Plug this hole by freeing the packet if
-EILSEQ is returned.
Signed-off-by: NSjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Do proper handling of dev_queue_xmit errors in order to
avoid double free of skb and leaks in error conditions.
In cfctrl pending requests are removed when CAIF Link layer goes down.
Signed-off-by: NSjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use struct net to reference CAIF configuration object instead of static variables.
Refactor functions caif_connect_client, caif_disconnect_client and squach
files cfcnfg.c and caif_config_utils.
Signed-off-by: NSjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

RCU read_lock and refcount is used to protect in-flight packets.

Use RCU and counters to manage freeing lower part of the CAIF stack if
CAIF-link layer is removed. Old solution based on delaying removal of
device is removed.

When CAIF link layer goes down the use of CAIF link layer is disabled
(by calling caif_set_phy_state()), but removal and freeing of the
lower part of the CAIF stack is done when Link layer is unregistered.
Signed-off-by: NSjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The variable 'caifdef' is set but unused in modemcmd().

Similarly for 'net' in receive(), and 'res' in
caif_device_notify() and caif_exit_net().

Just kill them off.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If CAIF Link Layer returns an error, we no longer try to re-build the
CAIF packet and resend it. Instead, we simply return any transmission
errors to the socket client.
Signed-off-by: NSjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Cleanup of new CAIF code.
  * make local functions static
  * remove code that is never used
  * expand get_caif_conf() since wrapper is no longer needed
  * make args to comparison functions const
  * rename connect_req_to_link_param to keep exported names
    consistent

Compile tested only.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Acked-by: NSjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Changes:
o Bugfix: SO_PRIORITY for SOL_SOCKET could not be handled
  in caif's setsockopt,  using the struct sock attribute priority instead.

o Bugfix: SO_BINDTODEVICE for SOL_SOCKET could not be handled
  in caif's setsockopt,  using the struct sock attribute ifindex instead.

o Wrong assert statement for RFM layer segmentation.

o CAIF Debug channels was not working over SPI, caif_payload_info
  containing padding info must be initialized.

o Check on pointer before dereferencing when unregister dev in caif_dev.c
Signed-off-by: NSjur Braendeland <sjur.brandeland@stericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Check that receive function pointer is not null before calling it.
Signed-off-by: NSjur Braendeland <sjur.brandeland@stericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Convert pr_<level>("%s" ..., (struct netdev *)->name ...)
to netdev_<level>((struct netdev *), ...)
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch standardizes caif message logging prefixes.

Add #define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
Add missing "\n"s to some logging messages
Convert pr_warning to pr_warn

This changes the logging message prefix from CAIF: to caif:
for all uses but caif_socket.c and chnl_net.c.  Those now use
their filename without extension.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Previously CAIF supported maximum transfer size of ~4050.
The transfer size is now calculated dynamically based on the
link layers mtu size.

Signed-off-by: Sjur Braendeland@stericsson.com
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch removes from net/ (but not any netfilter files)
all the unnecessary return; statements that precede the
last closing brace of void functions.

It does not remove the returns that are immediately
preceded by a label as gcc doesn't like that.

Done via:
$ grep -rP --include=*.[ch] -l "return;\n}" net/ | \
  xargs perl -i -e 'local $/ ; while (<>) { s/\n[ \t\n]+return;\n}/\n}/g; print; }'
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NSjur Braendeland <sjur.brandeland@stericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Changes:
o Added functions cfsrvl_get and cfsrvl_put.
o Added support release_client to use by socket and net device.
o Increase reference counting for in-flight packets from cfmuxl
Signed-off-by: NSjur Braendeland <sjur.brandeland@stericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Changes:
 o Renamed cfcnfg_del_adapt_layer to cfcnfg_disconn_adapt_layer
 o Fixed typo cfcfg to cfcnfg
 o Renamed linkid to channel_id
 o Updated documentation in caif_dev.h
 o Minor formatting changes
Signed-off-by: NSjur Braendeland <sjur.brandeland@stericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Registration and deregistration of CAIF Link Layer.
Signed-off-by: NSjur Braendeland <sjur.brandeland@stericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>