Fix build with CONFIG_SYSFS not enabled.
Signed-off-by: NTom Herbert <therbert@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch implements software receive side packet steering (RPS).  RPS
distributes the load of received packet processing across multiple CPUs.

Problem statement: Protocol processing done in the NAPI context for received
packets is serialized per device queue and becomes a bottleneck under high
packet load.  This substantially limits pps that can be achieved on a single
queue NIC and provides no scaling with multiple cores.

This solution queues packets early on in the receive path on the backlog queues
of other CPUs.   This allows protocol processing (e.g. IP and TCP) to be
performed on packets in parallel.   For each device (or each receive queue in
a multi-queue device) a mask of CPUs is set to indicate the CPUs that can
process packets. A CPU is selected on a per packet basis by hashing contents
of the packet header (e.g. the TCP or UDP 4-tuple) and using the result to index
into the CPU mask.  The IPI mechanism is used to raise networking receive
softirqs between CPUs.  This effectively emulates in software what a multi-queue
NIC can provide, but is generic requiring no device support.

Many devices now provide a hash over the 4-tuple on a per packet basis
(e.g. the Toeplitz hash).  This patch allow drivers to set the HW reported hash
in an skb field, and that value in turn is used to index into the RPS maps.
Using the HW generated hash can avoid cache misses on the packet when
steering it to a remote CPU.

The CPU mask is set on a per device and per queue basis in the sysfs variable
/sys/class/net/<device>/queues/rx-<n>/rps_cpus.  This is a set of canonical
bit maps for receive queues in the device (numbered by <n>).  If a device
does not support multi-queue, a single variable is used for the device (rx-0).

Generally, we have found this technique increases pps capabilities of a single
queue device with good CPU utilization.  Optimal settings for the CPU mask
seem to depend on architectures and cache hierarcy.  Below are some results
running 500 instances of netperf TCP_RR test with 1 byte req. and resp.
Results show cumulative transaction rate and system CPU utilization.

e1000e on 8 core Intel
   Without RPS: 108K tps at 33% CPU
   With RPS:    311K tps at 64% CPU

forcedeth on 16 core AMD
   Without RPS: 156K tps at 15% CPU
   With RPS:    404K tps at 49% CPU

bnx2x on 16 core AMD
   Without RPS  567K tps at 61% CPU (4 HW RX queues)
   Without RPS  738K tps at 96% CPU (8 HW RX queues)
   With RPS:    854K tps at 76% CPU (4 HW RX queues)

Caveats:
- The benefits of this patch are dependent on architecture and cache hierarchy.
Tuning the masks to get best performance is probably necessary.
- This patch adds overhead in the path for processing a single packet.  In
a lightly loaded server this overhead may eliminate the advantages of
increased parallelism, and possibly cause some relative performance degradation.
We have found that masks that are cache aware (share same caches with
the interrupting CPU) mitigate much of this.
- The RPS masks can be changed dynamically, however whenever the mask is changed
this introduces the possibility of generating out of order packets.  It's
probably best not change the masks too frequently.
Signed-off-by: NTom Herbert <therbert@google.com>

 include/linux/netdevice.h |   32 ++++-
 include/linux/skbuff.h    |    3 +
 net/core/dev.c            |  335 +++++++++++++++++++++++++++++++++++++--------
 net/core/net-sysfs.c      |  225 ++++++++++++++++++++++++++++++-
 net/core/skbuff.c         |    2 +
 5 files changed, 538 insertions(+), 59 deletions(-)
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The wireless sysfs methods like the rest of the networking sysfs
methods are removed with the rtnl_lock held and block until
the existing methods stop executing.  So use rtnl_trylock
and restart_syscall so that the code continues to work.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Generated with the following semantic patch

@@
struct net *n1;
struct net *n2;
@@
- n1 == n2
+ net_eq(n1, n2)

@@
struct net *n1;
struct net *n2;
@@
- n1 != n2
+ !net_eq(n1, n2)

applied over {include,net,drivers/net}.
Signed-off-by: NOctavian Purdila <opurdila@ixiacom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This isn't beautifully abstracted, but it is simple,
simplifies uses and so far is only needed for the bonding driver.
Signed-off-by: NEric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit d519e17e
(net: export device speed and duplex via sysfs)
made the wrong assumption that netdev->ethtool_ops was always set.

This makes possible to crash kernel and let rtnl in locked state.

modprobe dummy
ip link set dummy0 up
(udev runs and crash)
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Acked-by: NAndy Gospodarek <andy@greyhouse.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Refactor wext to
 * split out iwpriv handling
 * split out iwspy handling
 * split out procfs support
 * allow cfg80211 to have wireless extensions compat code
   w/o CONFIG_WIRELESS_EXT

After this, drivers need to
 - select WIRELESS_EXT	- for wext support
 - select WEXT_PRIV	- for iwpriv support
 - select WEXT_SPY	- for iwspy support

except cfg80211 -- which gets new hooks in wext-core.c
and can then get wext handlers without CONFIG_WIRELESS_EXT.

Wireless extensions procfs support is auto-selected
based on PROC_FS and anything that requires the wext core
(i.e. WIRELESS_EXT or CFG80211_WEXT).
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

A number of drivers (recently including cfg80211-based ones)
assume that all wireless handlers, including statistics, can
sleep and they often also implicitly assume that the rtnl is
held around their invocation. This is almost always true now
except when reading from sysfs:

  BUG: sleeping function called from invalid context at kernel/mutex.c:280
  in_atomic(): 1, irqs_disabled(): 0, pid: 10450, name: head
  2 locks held by head/10450:
   #0:  (&buffer->mutex){+.+.+.}, at: [<c10ceb99>] sysfs_read_file+0x24/0xf4
   #1:  (dev_base_lock){++.?..}, at: [<c12844ee>] wireless_show+0x1a/0x4c
  Pid: 10450, comm: head Not tainted 2.6.32-rc3 #1
  Call Trace:
   [<c102301c>] __might_sleep+0xf0/0xf7
   [<c1324355>] mutex_lock_nested+0x1a/0x33
   [<f8cea53b>] wdev_lock+0xd/0xf [cfg80211]
   [<f8cea58f>] cfg80211_wireless_stats+0x45/0x12d [cfg80211]
   [<c13118d6>] get_wireless_stats+0x16/0x1c
   [<c12844fe>] wireless_show+0x2a/0x4c

Fix this by using the rtnl instead of dev_base_lock.
Reported-by: NMiles Lane <miles.lane@gmail.com>
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch exports the link-speed (in Mbps) and duplex of an interface
via sysfs.  This eliminates the need to use ethtool just to check the
link-speed.  Not requiring 'ethtool' and not relying on the SIOCETHTOOL
ioctl should be helpful in an embedded environment where space is at a
premium as well.

NOTE: This patch also intentionally allows non-root users to check the link
speed and duplex -- something not possible with ethtool.

Here's some sample output:

# cat /sys/class/net/eth0/speed
100
# cat /sys/class/net/eth0/duplex
half
# ethtool eth0
Settings for eth0:
        Supported ports: [ TP ]
        Supported link modes:   10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
                                1000baseT/Half 1000baseT/Full
        Supports auto-negotiation: Yes
        Advertised link modes:  Not reported
        Advertised auto-negotiation: No
        Speed: 100Mb/s
        Duplex: Half
        Port: Twisted Pair
        PHYAD: 1
        Transceiver: internal
        Auto-negotiation: off
        Supports Wake-on: g
        Wake-on: g
        Current message level: 0x000000ff (255)
        Link detected: yes
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The move away from having drivers assign wireless handlers,
in favour of making cfg80211 assign them, broke the sysfs
registration (the wireless/ dir went missing) because the
handlers are now assigned only after registration, which is
too late.

Fix this by special-casing cfg80211-based devices, all
of which are required to have an ieee80211_ptr, in the
sysfs code, and also using get_wireless_stats() to have
the same values reported as in procfs.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Reported-by: NHugh Dickins <hugh.dickins@tiscali.co.uk>
Tested-by: NHugh Dickins <hugh.dickins@tiscali.co.uk>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Let attribute group vectors be declared "const".  We'd
like to let most attribute metadata live in read-only
sections... this is a start.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

String literals are constant, and usually, we can also tag the array
of pointers const too, moving it to the .rodata section.
Signed-off-by: NJan Engelhardt <jengelh@medozas.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

BUS_ID_SIZE is really no more, and device names are dynamically
allocated and thus can be any necessary size.

So remove the BUG check here making sure BUS_ID_SIZE is at least
as large as IFNAMSIZ.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The earlier patch to fix the deadlock between a network device going
away and writing to sysfs attributes was incomplete.
- It did not set signal_pending so we would leak ERSTARTSYS to user space.
- It used ERESTARTSYS which only restarts if sigaction configures it to.
- It did not cover store and show for ifalias.

So fix all of these up and use the new helper restart_syscall so we get
the details correct on what it takes.
Signed-off-by: NEric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since dev_set_name takes a printf style string, new gcc complains
if arg is not const.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Acked-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch will filter out the uevent not related to the init_net.
Without this patch if a network device is created in a network
namespace with the same name as one network device belonging to the
initial network namespace (eg. eth0), when the network namespace
will die and the network device will be destroyed, an event will
be sent and catched by the udevd daemon. That will result to have
the real network device to be shutdown because the udevd/uevent are
not namespace aware.
Signed-off-by: NDaniel Lezcano <dlezcano@fr.ibm.com>
Acked-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In order for the network device ops get_stats call to be immutable, the handling
of the default internal network device stats block has to be changed. Add a new
helper function which replaces the old use of internal_get_stats.

Note: change return code to make it clear that the caller should not
go changing the returned statistics.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NKay Sievers <kay.sievers@vrfy.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

To make testing of the network namespace simpler allow
the network namespace code and the sysfs code to be
compiled and run at the same time.  To do this only
virtual devices are allowed in the additional network
namespaces and those virtual devices are not placed
in the kobject tree.

Since virtual devices don't actually do anything interesting
hardware wise that needs device management there should
be no loss in keeping them out of the kobject tree and
by implication sysfs.  The gain in ease of testing
and code coverage should be significant.

Changelog:

v2: As pointed out by Benjamin Thery it only makes sense to call
    device_rename in the initial network namespace for now.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NBenjamin Thery <benjamin.thery@bull.net>
Tested-by: NSerge Hallyn <serue@us.ibm.com>
Acked-by: NSerge Hallyn <serue@us.ibm.com>
Acked-by: NDaniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch add support for keeping an additional character alias
associated with an network interface. This is useful for maintaining
the SNMP ifAlias value which is a user defined value. Routers use this
to hold information like which circuit or line it is connected to. It
is just an arbitrary text label on the network device.

There are two exposed interfaces with this patch, the value can be
read/written either via netlink or sysfs.

This could be maintained just by the snmp daemon, but it is more
generally useful for other management tools, and the kernel is good
place to act as an agreed upon interface to store it.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The /sys/class/net/*/wireless/ direcory is, as far as I know, not
used by anyone. Additionally, the same data is available via wext
ioctls. Hence the sysfs files are pretty much useless. This patch
makes them optional and schedules them for removal.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Cc: Jean Tourrilhes <jt@hpl.hp.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

	Permit bonding to function rationally if max_bonds is set to
zero.  This will load the module, but create no master devices (which can
be created via sysfs).

	Requires some change to bond_create_sysfs; currently, the
netdev sysfs directory is determined from the first bonding device created,
but this is no longer possible.  Instead, an interface from net/core is
created to create and destroy files in net_class.

	Based on a patch submitted by Phil Oester <kernel@linuxaces.com>.
Modified by Jay Vosburgh to fix the sysfs issue mentioned above and to
update the documentation.
Signed-off-by: NPhil Oester <kernel@linuxace.com>
Signed-off-by: NJay Vosburgh <fubar@us.ibm.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

And so does the pointer is returns, but sysfs and netlinks still 
check for both cases.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a netdev is moved across namespaces with the
'dev_change_net_namespace' function, the 'device_rename' function is
used to fixup kobject and refresh the sysfs tree. The device_rename
function will call kobject_rename and this one will check if there is
an object with the same name and this is the case because we are
renaming the object with the same name.

The use of 'device_rename' seems for me wrong because we usually don't
rename it but just move it across namespaces. As we just want to do a
mini "netdev_[un]register", IMO the functions
'netdev_[un]register_kobject' should be used instead, like an usual
network device [un]registering.

This patch replace device_rename by netdev_unregister_kobject,
followed by netdev_register_kobject.

The netdev_register_kobject will call device_initialize and will raise
a warning indicating the device was already initialized. In order to
fix that, I split the device initialization into a separate function
and use it together with 'netdev_register_kobject' into
register_netdevice. So we can safely call 'netdev_register_kobject' in
'dev_change_net_namespace'.

This fix will allow to properly use the sysfs per namespace which is
coming from -mm tree.
Signed-off-by: NDaniel Lezcano <dlezcano@fr.ibm.com>
Acked-by: NBenjamin Thery <benjamin.thery@bull.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Expose dev_id to userspace, because it helps to disambiguate between
interfaces where the MAC address is unique.

This should allow us to simplify the handling of persistent naming for
S390 network devices in udev -- because it can depend on a simple
attribute of the device like the other match criteria, rather than
having a special case for SUBSYSTEMS=="ccwgroup".
Signed-off-by: NDavid Woodhouse <dwmw2@infradead.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

print_mac() used many most net drivers and format_addr() used by
net-sysfs.c are very similar and they can be intergrated.

format_addr() is also identically redefined in the qla4xxx iscsi
driver.

Export a new function sysfs_format_mac() to be used by net-sysfs,
qla4xxx and others in the future.  Both print_mac() and
sysfs_format_mac() call _format_mac_addr() to do the formatting.

Changed print_mac() to use unsigned char * to be consistent with
net_device struct's dev_addr.  Added buffer length overrun checking
as suggested by Joe Perches.
Signed-off-by: NMichael Chan <mchan@broadcom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The

        if (statement)
                WARN_ON(1);

looks much better as

        WARN_ON(statement);
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Inconsistent prototype and real type for functions may have worse
consequences, than those for variables, so move them into a header.

Since they are used privately in net/core, make this file reside in
the same place.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This changes the uevent buffer functions to use a struct instead of a
long list of parameters. It does no longer require the caller to do the
proper buffer termination and size accounting, which is currently wrong
in some places. It fixes a known bug where parts of the uevent
environment are overwritten because of wrong index calculations.

Many thanks to Mathieu Desnoyers for finding bugs and improving the
error handling.
Signed-off-by: NKay Sievers <kay.sievers@vrfy.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

When sysfs support is compiled out the kernel still keeps and maintains
the kobject tree.  So it is not safe to skip our kobject reference counting or
to avoid becoming members of the kobject tree.  It is safe to not add
the networking specific sysfs attributes.

This patch removes the sysfs special cases from net/core/dev.c
renames functions from netdev_sysfs_xxxx to netdev_kobject_xxxx
and always compiles in net-sysfs.c

net-sysfs.c is modified with a CONFIG_SYSFS guard around the parts
that are actually sysfs specific.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Several devices have multiple independant RX queues per net
device, and some have a single interrupt doorbell for several
queues.

In either case, it's easier to support layouts like that if the
structure representing the poll is independant from the net
device itself.

The signature of the ->poll() call back goes from:

	int foo_poll(struct net_device *dev, int *budget)

to

	int foo_poll(struct napi_struct *napi, int budget)

The caller is returned the number of RX packets processed (or
the number of "NAPI credits" consumed if you want to get
abstract).  The callee no longer messes around bumping
dev->quota, *budget, etc. because that is all handled in the
caller upon return.

The napi_struct is to be embedded in the device driver private data
structures.

Furthermore, it is the driver's responsibility to disable all NAPI
instances in it's ->stop() device close handler.  Since the
napi_struct is privatized into the driver's private data structures,
only the driver knows how to get at all of the napi_struct instances
it may have per-device.

With lots of help and suggestions from Rusty Russell, Roland Dreier,
Michael Chan, Jeff Garzik, and Jamal Hadi Salim.

Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra,
Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan.

[ Ported to current tree and all drivers converted.  Integrated
  Stephen's follow-on kerneldoc additions, and restored poll_list
  handling to the old style to fix mutual exclusion issues.  -DaveM ]
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Kenji Kaneshige found this race between device removal and
registration.  On unregister it is possible for the old device to
exist, because sysfs file is still open.  A new device with 'eth%d'
will select the same name, but sysfs kobject register will fial.

The following changes the shutdown order slightly. It hold a removes
the sysfs entries earlier (on unregister_netdevice), but holds a
kobject reference.  Then when todo runs the actual last put free
happens.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Make use of add_uevent_var() instead of (often incorrectly) open coding it.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NEric Rannaud <eric.rannaud@gmail.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Provide rename event for when we rename network devices.
Signed-off-by: NJean Tourrilhes <jt@hpl.hp.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

 

Fix whitespace around keywords. Fix indentation especially of switch
statements.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Rename the (apparently) incorrect macro name WIRELESS_EXT to
CONFIG_WIRELESS_EXT.
Signed-off-by: NRobert P. J. Day <rpjday@mindspring.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This lets the network core have the ability to handle suspend/resume
issues, if it wants to.

Thanks to Frederik Deweerdt <frederik.deweerdt@gmail.com> for the arm
driver fixes.
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This is version 21 of the Wireless Extensions. Changelog :
	o finishes migrating the ESSID API (remove the +1)
	o netdev->get_wireless_stats is no more
	o long/short retry

This is a redacted version of a patch originally submitted by Jean
Tourrilhes.  I removed most of the additions, in order to minimize
future support requirements for nl80211 (or other WE successor).

CC: Jean Tourrilhes <jt@hpl.hp.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>