cdc_ncm disagrees with usbnet about how much framing overhead should
be counted in the tx_bytes statistics, and tries 'fix' this by
decrementing tx_bytes on the transmit path.  But statistics must never
be decremented except due to roll-over; this will thoroughly confuse
user-space.  Also, tx_bytes is only incremented by usbnet in the
completion path.

Fix this by requiring drivers that set FLAG_MULTI_FRAME to set a
tx_bytes delta along with the tx_packets count.

Fixes: beeecd42 ("net: cdc_ncm/cdc_mbim: adding NCM protocol statistics")
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NBjørn Mork <bjorn@mork.no>

Currently the usbnet core does not update the tx_packets statistic for
drivers with FLAG_MULTI_PACKET and there is no hook in the TX
completion path where they could do this.

cdc_ncm and dependent drivers are bumping tx_packets stat on the
transmit path while asix and sr9800 aren't updating it at all.

Add a packet count in struct skb_data so these drivers can fill it
in, initialise it to 1 for other drivers, and add the packet count
to the tx_packets statistic on completion.
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Tested-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently the usbnet core does not update the tx_packets statistic for
drivers with FLAG_MULTI_PACKET and there is no hook in the TX
completion path where they could do this.

cdc_ncm and dependent drivers are bumping tx_packets stat on the
transmit path while asix and sr9800 aren't updating it at all.

Add a packet count in struct skb_data so these drivers can fill it
in, initialise it to 1 for other drivers, and add the packet count
to the tx_packets statistic on completion.
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Tested-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

To delegate promiscuous mode and multicast filtering to the subdriver.
Signed-off-by: NOlivier Blin <olivier.blin@softathome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This device needs to be reset to recover from a timeout.
Unfortunately this can be handled only at the level of
the subdrivers.
Signed-off-by: NOliver Neukum <oneukum@suse.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts commit 20fbe3ae.

As reported by Stephen Rothwell, it causes compile failures in certain
configurations:

  drivers/net/usb/cdc_subset.c:360:15: error: 'dummy_prereset' undeclared here (not in a function)
    .pre_reset = dummy_prereset,
                 ^
  drivers/net/usb/cdc_subset.c:361:16: error: 'dummy_postreset' undeclared here (not in a function)
    .post_reset = dummy_postreset,
                  ^
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Acked-by: NDavid Miller <davem@davemloft.net>
Cc: Oliver Neukum <oneukum@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This device needs to be reset to recover from a timeout.
Unfortunately this can be handled only at the level of
the subdrivers.
Signed-off-by: NOliver Neukum <oneukum@suse.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This fixes a race which happens by freeing an object on the stack.
Quoting Julius:
> The issue is
> that it calls usbnet_terminate_urbs() before that, which temporarily
> installs a waitqueue in dev->wait in order to be able to wait on the
> tasklet to run and finish up some queues. The waiting itself looks
> okay, but the access to 'dev->wait' is totally unprotected and can
> race arbitrarily. I think in this case usbnet_bh() managed to succeed
> it's dev->wait check just before usbnet_terminate_urbs() sets it back
> to NULL. The latter then finishes and the waitqueue_t structure on its
> stack gets overwritten by other functions halfway through the
> wake_up() call in usbnet_bh().

The fix is to just not allocate the data structure on the stack.
As dev->wait is abused as a flag it also takes a runtime PM change
to fix this bug.
Signed-off-by: NOliver Neukum <oneukum@suse.de>
Reported-by: NGrant Grundler <grundler@google.com>
Tested-by: NGrant Grundler <grundler@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 638c5115(USBNET: support DMA SG) introduces DMA SG
if the usb host controller is capable of building packet from
discontinuous buffers, but missed handling padding packet when
building DMA SG.

This patch attachs the pre-allocated padding packet at the
end of the sg list, so padding packet can be sent to device
if drivers require that.
Reported-by: NDavid Laight <David.Laight@aculab.com>
Acked-by: NOliver Neukum <oliver@neukum.org>
Signed-off-by: NMing Lei <ming.lei@canonical.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch introduces support of DMA SG if the USB host controller
which usbnet device is attached to is capable of building packet from
discontinuous buffers.

The patch supports passing the skb fragment buffers to usb stack directly
via urb->sg.

Cc: Ben Hutchings <bhutchings@solarflare.com>
Cc: Grant Grundler <grundler@google.com>
Cc: Freddy Xin <freddy@asix.com.tw>
Cc: Alan Stern <stern@rowland.harvard.edu>
Acked-by: NOliver Neukum <oneukum@suse.de>
Signed-off-by: NMing Lei <ming.lei@canonical.com>
Reviewed-by: NEric Dumazet <edumazet@google.com>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch centralizes computing of max rx/tx qlen, because:

- RX_QLEN()/TX_QLEN() is called in hot path
- computing depends on device's usb speed, now we have ls/fs, hs, ss,
so more checks need to be involved
- in fact, max rx/tx qlen should not only depend on device USB
speed, but also depend on ethernet link speed, so we need to
consider that in future.
- if SG support is done, max tx qlen may need change too

Generally, hard_mtu and rx_urb_size are changed in bind(), reset()
and link_reset() callback, and change mtu network operation, this
patches introduces the API of usbnet_update_max_qlen(), and calls
it in above path.
Signed-off-by: NMing Lei <ming.lei@canonical.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some drivers (sierra_net) need the status interrupt URB
active even when the device is closed, because they receive
custom indications from firmware.  Add functions to refcount
the status interrupt URB submit/kill operation so that
sub-drivers and the generic driver don't fight over whether
the status interrupt URB is active or not.

A sub-driver can call usbnet_status_start() at any time, but
the URB is only submitted the first time the function is
called.  Likewise, when the sub-driver is done with the URB,
it calls usbnet_status_stop() but the URB is only killed when
all users have stopped it.  The URB is still killed and
re-submitted for suspend/resume, as before, with the same
refcount it had at suspend.
Signed-off-by: NDan Williams <dcbw@redhat.com>
Acked-by: NOliver Neukum <oliver@neukum.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The link change is detected via the interrupt pipe, and bulk
pipes are responsible for transfering packets, so it is reasonable
to stop bulk transfer after link is reported as off.

Two adavantages may be obtained with stopping bulk transfer
after link becomes off:

- USB bus bandwidth is saved(USB bus is shared bus except for
USB3.0), for example, lots of 'IN' token packets and 'NYET'
handshake packets is transfered on 2.0 bus.

- probabaly power might be saved for usb host controller since
cancelling bulk transfer may disable the asynchronous schedule of
host controller.

With this patch, when link becomes off, about ~10% performance
boost can be found on bulk transfer of anther usb device which
is attached to same bus with the usbnet device, see below
test on next-20130410:

- read from usb mass storage(Sandisk Extreme USB 3.0) on pandaboard
with below command after unplugging ethernet cable:

	dd if=/dev/sda iflag=direct of=/dev/null bs=1M count=800

- without the patch
1, 838860800 bytes (839 MB) copied, 36.2216 s, 23.2 MB/s
2, 838860800 bytes (839 MB) copied, 35.8368 s, 23.4 MB/s
3, 838860800 bytes (839 MB) copied, 35.823 s, 23.4 MB/s
4, 838860800 bytes (839 MB) copied, 35.937 s, 23.3 MB/s
5, 838860800 bytes (839 MB) copied, 35.7365 s, 23.5 MB/s
average: 23.6MB/s

- with the patch
1, 838860800 bytes (839 MB) copied, 32.3817 s, 25.9 MB/s
2, 838860800 bytes (839 MB) copied, 31.7389 s, 26.4 MB/s
3, 838860800 bytes (839 MB) copied, 32.438 s, 25.9 MB/s
4, 838860800 bytes (839 MB) copied, 32.5492 s, 25.8 MB/s
5, 838860800 bytes (839 MB) copied, 31.6178 s, 26.5 MB/s
average: 26.1MB/s
Signed-off-by: NMing Lei <ming.lei@canonical.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch introduces the API of usbnet_link_change, so that
usbnet can handle link change centrally, which may help to
implement killing traffic URBs for saving USB bus bandwidth
and host controller power.
Signed-off-by: NMing Lei <ming.lei@canonical.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In commit 6509141f ("usbnet: add new
flag FLAG_NOARP for usb net devices"), the newly added flag NOARP was
using an already defined value, which broke drivers using flag
MULTI_PACKET.
Signed-off-by: NLucas Stach <dev@lynxeye.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A device sending 0 length frames as fast as it can has been
observed killing the host system due to the resulting memory
pressure.

Temporarily disable RX skb allocation and URB submission when
the current error ratio is high, preventing us from trying to
allocate an infinite number of skbs.  Reenable as soon as we
are finished processing the done queue, allowing the device
to continue working after short error bursts.
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Acked-by: NOliver Neukum <oneukum@suse.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We do have some USB net devices, which cannot do ARP.
so we can introduce a new flag FLAG_NOARP, then client drivers
can easily handle this kind of devices
Signed-off-by: NWei Shuai <cpuwolf@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Centralise common code for manage_power() in usbnet
by making a generic simple implementation
Signed-off-by: NOliver Neukum <oneukum@suse.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If a device fails to do remote wakeup, this is no reason
to abort an open totally. This patch just continues without
runtime PM.
Signed-off-by: NOliver Neukum <oneukum@suse.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch introduces the below two helpers to prepare for solving
the usbnet runtime PM problem, which may cause some network utilities
(ifconfig, ethtool,...) touch a suspended device.

	usbnet_read_cmd_nopm()
	usbnet_write_cmd_nopm()

The above two helpers should be called by usbnet resume/suspend
callback to avoid deadlock.
Signed-off-by: NMing Lei <ming.lei@canonical.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch introduces the below 3 usb command helpers:

	usbnet_read_cmd / usbnet_write_cmd / usbnet_write_cmd_async

so that each low level driver doesn't need to implement them
by itself, and the dma buffer allocation for usb transfer and
runtime PM things can be handled just in one place.
Acked-by: NOliver Neukum <oneukum@suse.de>
Signed-off-by: NMing Lei <ming.lei@canonical.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some device types support a form of power management in which
the device suggests to the host that the device may be suspended
now. Support for that is best located in usbnet.
Signed-off-by: NOliver Neukum <oneukum@suse.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The flag of EVENT_DEV_WAKING is not used any more, so just remove it.
Signed-off-by: NMing Lei <tom.leiming@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 4231d47e(net/usbnet: avoid
recursive locking in usbnet_stop()) fixes the recursive locking
problem by releasing the skb queue lock before unlink, but may
cause skb traversing races:
	- after URB is unlinked and the queue lock is released,
	the refered skb and skb->next may be moved to done queue,
	even be released
	- in skb_queue_walk_safe, the next skb is still obtained
	by next pointer of the last skb
	- so maybe trigger oops or other problems

This patch extends the usage of entry->state to describe 'start_unlink'
state, so always holding the queue(rx/tx) lock to change the state if
the referd skb is in rx or tx queue because we need to know if the
refered urb has been started unlinking in unlink_urbs.

The other part of this patch is based on Huajun's patch:
always traverse from head of the tx/rx queue to get skb which is
to be unlinked but not been started unlinking.
Signed-off-by: NHuajun Li <huajun.li.lee@gmail.com>
Signed-off-by: NMing Lei <tom.leiming@gmail.com>
Cc: Oliver Neukum <oneukum@suse.de>
Cc: stable@kernel.org
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Resubmit interrupt URB if device is open.  Use a flag set in
usbnet_open() to determine this state.  Also kill and free
interrupt URB in usbnet_disconnect().

[Rebased off git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git]
Signed-off-by: NPaul Stewart <pstew@chromium.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

USB tethering does not work anymore since 2.6.39-rc2, but it's okay in
-rc1. The root cause is the new added mask code 'FLAG_POINTTOPOINT'
overlaps 'FLAG_MULTI_PACKET'  in  include/linux/usb/usbnet.h, this
causes logic issue in  rx_process(). This patch cleans up the overlap.
Reported-and-Tested-by: NGottfried Haider <gottfried.haider@gmail.com>
Signed-off-by: NHuajun Li <huajun.li.lee@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The documentation for the USB ethernet devices suggests that
only some devices are supposed to use usb0 as the network interface
name instead of eth0. The logic used there, and documented in
Kconfig for CDC is that eth0 will be used when the mac address
is a globally assigned one, but usb0 is used for the locally
managed range that is typically used on point-to-point links.

Unfortunately, this has caused a lot of pain on the smsc95xx
device that is used on the popular pandaboard without an
EEPROM to store the MAC address, which causes the driver to
call random_ether_address().

Obviously, there should be a proper MAC addressed assigned to
the device, and discussions are ongoing about how to solve
this, but this patch at least makes sure that the default
interface naming gets a little saner and matches what the
user can expect based on the documentation, including for
new devices.

The approach taken here is to flag whether a device might be a
point-to-point link with the new FLAG_POINTTOPOINT setting in
the usbnet driver_info. A driver can set both FLAG_POINTTOPOINT
and FLAG_ETHER if it is not sure (e.g. cdc_ether), or just one
of the two.  The usbnet framework only looks at the MAC address
for device naming if both flags are set, otherwise it trusts the
flag.
Signed-off-by: NArnd Bergmann <arnd.bergmann@linaro.org>
Tested-by: NAndy Green <andy.green@linaro.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This adds a driver for the CDC Ethernet part of this modem.  The
device's ID is blacklisted in cdc_ether.c and is white-listed in
this new driver because of the quirks needed to make it useful.
The modem's firmware exposes a CDC ACM port for modem control and a
CDC Ethernet port for network data.  The descriptors look fine but
both ports actually are some sort of multiplexers requiring non-
standard headers added/removed from every packet or they get
ignored.  All information is based on a usb traffic log from a
Windows machine.

On the Verizon 4G network I've seen speeds up to 1.1MB/s so far with
this driver, a speed-o-meter site reports 16.2Mbps/10.5Mbps.
Userspace scripts are required to talk to the CDC ACM port.
Signed-off-by: NAndrzej Zaborowski <balrogg@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Changes:
include/linux/usb/usbnet.h:
- a new flag to indicate driver's capability to accumulate IP packets in Tx
 direction and extract several packets from single skb in Rx direction.
drivers/net/usb/usbnet.c:
- the procedure of counting packets in usbnet was updated due to the
 accumulating of IP packets in the driver
- no short packets are sent if indicated by the flag in driver_info
 structure
Signed-off-by: NAlexey Orishko <alexey.orishko@stericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Lots of minor formatting cleanups in includes/usb/ to make checkpatch
happier.
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

These macros are too similar to the dev_<level> equivalents
but take a usbnet * argument.  Convert them to the recently
introduced netdev_<level> macros and remove the old macros.

The old macros had "\n" appended to the format string.
Add the "\n" to the converted uses.

Some existing uses of the dev<foo> macros in cdc_eem.c
probably mistakenly had trailing "\n".  No "\n" added there.

Fix net1080 this/other log message inversion.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Using remote wakeup and delayed transmission to allow
online device to go into usb autosuspend.
Minimal alternate support for devices that don't support
remote wakeup.
Signed-off-by: NOliver Neukum <oliver@neukum.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some usbnet drivers update link state while others do not due to
hardware limitations.  Add a flag to distinguish those that do, and
set the link down initially for their devices.

This is intended to fix this bug: http://bugs.debian.org/444043Signed-off-by: NBen Hutchings <ben@decadent.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add support for usbnet based devices like CDC-Ether to indicate that they
are actually mobile broadband devices. In that case use wwan%d as default
interface name.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Usbnet framework assumes USB hardware doesn't handle zero length
packets, but SMSC LAN95xx requires these to be sent for correct
operation.

This patch fixes an easily reproducible tx lockup when sending a frame
that results in exactly 512 bytes in a USB transmission (e.g. a UDP
frame with 458 data bytes, due to IP headers and our USB headers).  It
adds an extra flag to usbnet for the hardware driver to indicate that
it can handle and requires the zero length packets.

This patch should not affect other usbnet users, please also consider
for -stable.
Signed-off-by: NSteve Glendinning <steve.glendinning@smsc.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add rx queue pausing to usbnet. This is needed by rndis_wlan so that it can
control rx queue and prevent received packets from being send forward before
rndis_wlan receives and handles 'media connect'-indication. Without this
establishing WPA connections is hard and fail often.

[v2] - removed unneeded use of skb_clone

Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Allow rndis_wlan to see all indications. Currently rndis_host lets rndis_wlan to
know about link state changes only, but there is whole set of other
802.11-specific indications that rndis_wlan should handle properly. So rename
link_change() to indication() and convert rndis_wlan to use it.
Signed-off-by: NJussi Kivilinna <jussi.kivilinna@mbnet.fi>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

rndis_wlan devices freeze after running usbnet_stop several times. It appears
that firmware freezes in state where it does not respond to any RNDIS commands
and device have to be physically unplugged/replugged. This patch lets
minidrivers to disable unlink_urbs on usbnet_stop through new info flag.
Signed-off-by: NJussi Kivilinna <jussi.kivilinna@mbnet.fi>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Allow minidriver to know that netdev has stopped. This is to let
wireless turn off radio when usbnet dev is stopped.
Signed-off-by: NJussi Kivilinna <jussi.kivilinna@mbnet.fi>
Acked-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>