What it is: vhost net is a character device that can be used to reduce
the number of system calls involved in virtio networking.
Existing virtio net code is used in the guest without modification.

There's similarity with vringfd, with some differences and reduced scope
- uses eventfd for signalling
- structures can be moved around in memory at any time (good for
  migration, bug work-arounds in userspace)
- write logging is supported (good for migration)
- support memory table and not just an offset (needed for kvm)

common virtio related code has been put in a separate file vhost.c and
can be made into a separate module if/when more backends appear.  I used
Rusty's lguest.c as the source for developing this part : this supplied
me with witty comments I wouldn't be able to write myself.

What it is not: vhost net is not a bus, and not a generic new system
call. No assumptions are made on how guest performs hypercalls.
Userspace hypervisors are supported as well as kvm.

How it works: Basically, we connect virtio frontend (configured by
userspace) to a backend. The backend could be a network device, or a tap
device.  Backend is also configured by userspace, including vlan/mac
etc.

Status: This works for me, and I haven't see any crashes.
Compared to userspace, people reported improved latency (as I save up to
4 system calls per packet), as well as better bandwidth and CPU
utilization.

Features that I plan to look at in the future:
- mergeable buffers
- zero copy
- scalability tuning: figure out the best threading model to use

Note on RCU usage (this is also documented in vhost.h, near
private_pointer which is the value protected by this variant of RCU):
what is happening is that the rcu_dereference() is being used in a
workqueue item.  The role of rcu_read_lock() is taken on by the start of
execution of the workqueue item, of rcu_read_unlock() by the end of
execution of the workqueue item, and of synchronize_rcu() by
flush_workqueue()/flush_work(). In the future we might need to apply
some gcc attribute or sparse annotation to the function passed to
INIT_WORK(). Paul's ack below is for this RCU usage.

(Includes fixes by Alan Cox <alan@linux.intel.com>,
David L Stevens <dlstevens@us.ibm.com>,
Chris Wright <chrisw@redhat.com>)
Acked-by: NRusty Russell <rusty@rustcorp.com.au>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: N"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

vhost net module wants to do copy to/from user from a kernel thread,
which needs use_mm. Export it to modules.
Acked-by: NAndrea Arcangeli <aarcange@redhat.com>
Acked-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Tun device looks similar to a packet socket
in that both pass complete frames from/to userspace.

This patch fills in enough fields in the socket underlying tun driver
to support sendmsg/recvmsg operations, and message flags
MSG_TRUNC and MSG_DONTWAIT, and exports access to this socket
to modules.  Regular read/write behaviour is unchanged.

This way, code using raw sockets to inject packets
into a physical device, can support injecting
packets into host network stack almost without modification.

First user of this interface will be vhost virtualization
accelerator.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Acked-by: NHerbert Xu <herbert@gondor.apana.org.au>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds error checking of ctrlmode values for CAN devices. As
an example all availabe bits are implemented in the mcp251x driver.
Signed-off-by: NChristian Pellegrin <chripell@fsfe.org>
Acked-by: NWolfgang Grandegger <wg@grandegger.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NAmit Kumar Salecha <amit.salecha@qlogic.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

GNU General Public License is in file "COPYING".
Signed-off-by: NAmit Kumar Salecha <amit.salecha@qlogic.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Before sending Interrupt coalesce parameters to device,
convert them in little endian.
Signed-off-by: NAmit Kumar Salecha <amit.salecha@qlogic.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In netxen_read_mac_addr, mac_addr should be declared
u64 instead of __le64, used by host only.
Signed-off-by: NAmit Kumar Salecha <amit.salecha@qlogic.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As noticed by H Hartley Sweeten, since change_nexthops() uses 'nh'
as it's iterator variable, it can conflict with other existing
local vars.

Use "nexthop_nh" to avoid the conflict and make it easier to figure
out where this magic variable comes from.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In sock_getsockopt the symbol 'lv' is declared as an
unsigned int type, probably due to sizeof returning a
size_t which is really an unsigned int.

This produces a sparse warning for SO_PEERNAME due to
the sock->ops->getname() call:

warning: incorrect type in argument 3 (different signedness)
   expected int *sockaddr_len
   got unsigned int *<noident>

Quiet the warning by changing the type of 'lv' to an int.
Signed-off-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Convert code away from ->read_proc/->write_proc interfaces.  Switch to
proc_create()/proc_create_data() which make addition of proc entries
reliable wrt NULL ->proc_fops, NULL ->data and so on.

Problem with ->read_proc et al is described here commit
786d7e16 "Fix rmmod/read/write races in
/proc entries"

[akpm@linux-foundation.org: CONFIG_PROC_FS=n build fix]
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NTilman Schmidt <tilman@imap.cc>
Signed-off-by: NKarsten Keil <keil@b1-systems.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDaniel Borkmann <danborkmann@googlemail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

there is a unnecessary test which can be replaced by a good initialization in
the 'for' statement

Noticed by Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: NSamir Bellabes <sam@synack.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Set default BLKT values for new OSA/3 hardware.
Signed-off-by: NEinar Lueck <elelueck@de.ibm.com>
Signed-off-by: NFrank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If a qeth device is set online, several initialisation steps are
performed. If a failure in one of these steps occurs, the qeth
device is reset into DOWN state. If due to the failure a qeth recovery
is scheduled and started in another thread, this might cause all kinds
of conflicts, even a kernel panic. The patch forbids scheduling of a
qeth recovery while online processing is performed till the card is in
state SOFTSETUP.
Signed-off-by: NUrsula Braun <ursula.braun@de.ibm.com>
Signed-off-by: NFrank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

New feature to trace HiperSockets network traffic for debugging
purposes.
Signed-off-by: NUrsula Braun <ursula.braun@de.ibm.com>
Signed-off-by: NFrank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Make updating the multicast address list generic for all families and
enforce the requirement to update the entire multicast table array all at
once instead of piecemeal which causes problems on some parts.
Signed-off-by: NBruce Allan <bruce.w.allan@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Provide MAC-specific function pointer to determine the LAN ID (PCI func).
The LAN ID is used internally by the driver to determine which h/w lock
to use to protect accessing the PHY on ESB2 as well as help to determine
the alternate MAC address on some parts.
Signed-off-by: NBruce Allan <bruce.w.allan@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Similar to 82571/2/3 parts that already do this, if ESB2/80003es2lan parts
have an alternate MAC address provided in the EEPROM use it instead of the
default MAC address.  This patch makes the the actual code that does this
generic so that it can be better used by both MAC families.
Signed-off-by: NBruce Allan <bruce.w.allan@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This should allow the removal of the #defines and uses
of NIPQUAD and NIPQUAD_FMT
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

To prevent the CAN drivers to operate on invalid socketbuffers the skbs are
now checked and silently dropped at the xmit-function consistently.

Also the netdev stats are consistently using the CAN data length code (dlc)
for [rx|tx]_bytes now.
Signed-off-by: NOliver Hartkopp <oliver@hartkopp.net>
Acked-by: NWolfgang Grandegger <wg@grandegger.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds the kernel portions needed to implement
RFC 5082 Generalized TTL Security Mechanism (GTSM).
It is a lightweight security measure against forged
packets causing DoS attacks (for BGP). 

This is already implemented the same way in BSD kernels.
For the necessary Quagga patch 
  http://www.gossamer-threads.com/lists/quagga/dev/17389

Description from Cisco
  http://www.cisco.com/en/US/docs/ios/12_3t/12_3t7/feature/guide/gt_btsh.html

It does add one byte to each socket structure, but I did
a little rearrangement to reuse a hole (on 64 bit), but it
does grow the structure on 32 bit

This should be documented on ip(4) man page and the Glibc in.h
file also needs update.  IPV6_MINHOPLIMIT should also be added
(although BSD doesn't support that).  

Only TCP is supported, but could also be added to UDP, DCCP, SCTP
if desired.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Conflicts:
	drivers/net/benet/be_cmds.h
	include/linux/sysctl.h

pci_dma_mapping_error should be used to test return value of
pci_map_single or pci_map_page.
Signed-off-by: NDenis Kirjanov <kirjanov@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Skip MAC loopback test when the adapter is set to a VT mode such as SR-IOV
or VMDq
Signed-off-by: NGreg Rose <gregory.v.rose@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Adds SR-IOV features supported by the 82599 controller to the main driver
module.  If the CONFIG_PCI_IOV kernel option is selected then the SR-IOV
features are enabled.  Use the max_vfs module option to allocate up to 63
virtual functions per physical port.
Signed-off-by: NGreg Rose <gregory.v.rose@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Adds code to the core 82599 module to support SR-IOV features of the 82599
network controller
Signed-off-by: NGreg Rose <gregory.v.rose@intel.com>
Acked-by: NPeter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add the mailbox and SR-IOV feature modules to the ixgbe driver Makefile.
Signed-off-by: NGreg Rose <gregory.v.rose@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This module and header file add functions to support SR-IOV features of the
82599 10Gbe controller.
Signed-off-by: NGreg Rose <gregory.v.rose@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds register definitions, bit definitions and structures used by
the driver to support SR-IOV features of the 82599 controller.
Signed-off-by: NGreg Rose <gregory.v.rose@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The 82599 virtual function device and the master 82599 physical function
device implement a mailbox utility for communication between the devices
using some SRAM scratch memory and a doorbell/answering mechanism enabled
via interrupt and/or polling.  This C module and accompanying header
file implement the base functions for use of this feature.
Signed-off-by: NGreg Rose <gregory.v.rose@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Modifications for the Kconfig and network device Makefile to add the ixgbevf
driver module to the kernel plus basic driver documentation.
Signed-off-by: NGreg Rose <gregory.v.rose@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

82599 Virtual Function Device Driver Makefile
Signed-off-by: NGreg Rose <gregory.v.rose@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These modules and header contain the Linux OS network interface code and core
interrupt and network send/receive handlers.
Signed-off-by: NGreg Rose <gregory.v.rose@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The 82599 virtual function device and the master 82599 physical function
device implement a mailbox utility for communication between the devices
using some SRAM scratch memory and a doorbell/answering mechanism enabled
via interrupt and/or polling.  This C module and accompanying header
file implement the base functions for use of this feature.
Signed-off-by: NGreg Rose <gregory.v.rose@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This module and header file contain the core functions for the 82599
virtual function device.
Signed-off-by: NGreg Rose <gregory.v.rose@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These two headers define the commonly used macros, data structures,
register bits and register offsets used by the ixgbevf driver on the
82599 virtual function device
Signed-off-by: NGreg Rose <gregory.v.rose@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Stanse found a potential null dereference in ircomm_tty_close
and ircomm_tty_hangup. There is a check for tty being NULL,
but it is dereferenced earlier. But it is bogus, the tty cannot
be NULL, so remove the !tty checks.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: netdev@vger.kernel.org
Signed-off-by: NDavid S. Miller <davem@davemloft.net>