Bjørn Mork says:

====================
net: qmi_wwan: MDM9x30 support

We add new device IDs all the time, often without any testing on
actual hardware. This is usually OK as long as the device is similar
to already supported devices, using the same chipset and firmware
basis.  But the Sierra Wireless MC7455 is an example of a new chipset
generation. Adding it based on assumed similarity with its ancestors
proved too optimistic.

This series adds the missing bits and pieces necessary to support LTE
Advanced modems based on the Qualcomm MDM9x30 chipset. A big thanks to
Sierra Wireless for providing MC7455 samples for testing

The most important change is the "raw-ip" support. The series also
adds a necessary control request, removes an unsupported device ID,
and adds a driver specific entry in MAINTAINERS.

A few random notes about "raw-ip":

"I rather have these all running in raw IP mode. The 802.3 framing is
utterly stupid." - Marcel Holtmann in Jan 2012 [1]

Marcel was right.  I should have listened to him. What more can I say?

The 802.3 framing has provided a steady supply of firmware bugs for
many years. We've added driver workarounds for many of these, but
there are still known bugs where the workaround is so yucky that we
have refused to apply it. But all that is over now.  The latest
generation Qualcomm chips no longer supports 802.3 framing at all.

I had two open questions regarding the "raw-ip" userspace API:

1) Should we continue faking an ethernet device, even if we don't use
   the L2 headers on the USB link anymore?

   There was a vote in favour of the "headerless" device. This is the
   honest representation of the hardware/firmware interface.

2) What input should the driver base its framing on?

   Snooping or directly manipulating QMI is considered out of the
   question. We delegated all QMI handling to userspace from the
   beginning.

   We have so far required userspace to configure the firmware for
   "802.3" framing, or fail if that proved impossible.  This
   requirement is now changed.  Userspace must now inform the driver
   if it negotiates "raw-ip" framing.  Two alternative interfaces were
   proposed:
    - ethtool private driver flag, or
    - sysfs file

   The NetworkManager/ModemManager developers were in favour of the
   sysfs alternative.

These questions (or any other you migh have :) are of course still
open.  This patch set presents the solutions I currently prefer,
considering the above.

All comments are appreciated, even simple '+1' ones.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>

QMI wwan devices have traditionally emulated ethernet devices
by default. But they have always had the capability of operating
without any L2 header at all, transmitting and receiving "raw"
IP packets over the USB link.  This firmware feature used to be
configurable through the QMI management protocol.

Traditionally there was no way to verify the firmware mode
without attempting to change it.  And the firmware would often
disallow changes anyway, i.e. due to a session already being
established.  In some cases, this could be a hidden firmware
internal session, completely outside host control.  For these
reasons, sticking with the "well known" default mode was safest.

But newer generations of QMI hardware and firmware have moved
towards defaulting to "raw IP" mode instead, followed by an
increasing number of bugs in the already buggy "802.3" firmware
implementation. At the same time, the QMI management protocol
gained the ability to detect the current mode.  This has enabled
the userspace QMI management application to verify the current
firmware mode without trying to modify it.

Following this development, the latest QMI hardware and firmware
(the MDM9x30 generation) has dropped support for "802.3" mode
entirely. Support for "raw IP" framing in the driver is therefore
necessary for these devices, and to a certain degree to work
around problems with the previous generation,

This patch adds support for "raw IP" framing for QMI devices,
changing the netdev from an ethernet device to an ARPHRD_NONE
p-t-p device when "raw IP" framing is enabled.

The firmware setup is fully delegated to the QMI userspace
management application, through simple tunneling of the QMI
protocol. The driver will therefore not know which mode has been
"negotiated" between firmware and userspace. Allowing userspace
to inform the driver of the result through a sysfs switch is
considered a better alternative than to change the well established
clean delegation of firmware management to userspace.
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>

Assume the minidriver has taken care of all L2 header parsing
if it sets skb->protocol.  This allows the minidriver to
support non-ethernet L2 headers, and even operate without
any L2 header at all.
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This turned out to be a bootloader device ID.  No need for
that in this driver.  It will only provide a single serial
function.
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>

MDM9x30 based modems appear to go into a deeper sleep when
suspended without "Remote Wakeup" enabled.  The QMI interface
will not respond unless a "set DTR" control request is sent
on resume. The effect is similar to a QMI_CTL SYNC request,
resetting (some of) the firmware state.

We allow userspace sessions to span multiple character device
open/close sequences.  This means that userspace can depend
on firmware state while both the netdev and the character
device are closed.  We have disabled "needs_remote_wakeup" at
this point to allow devices without remote wakeup support to
be auto-suspended.

To make sure the MDM9x30 keeps firmware state, we need to
keep "needs_remote_wakeup" always set. We also need to
issue a "set DTR" request to enable the QMI interface.
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>

Salil Mehta says:

====================
net:hns: Add support of Hip06 SoC to the Hislicon Network Subsystem

This PATCH V7 addresses the TAB formatting comments by
Sergei Shtylyov. Missing TABs at some other palces have
also been corrected.

PATCH V6:
This addresses the review comments provided by
David Miller over the existing use of ENABLE/DISABLE
hash defines with the code. These hash defines are doing
a similar job as implicit type bool would do. So these are
kind of duplicate and are redundant.

PATCH V5:
This PATCH addresses the review comments by Yuval Mintz
 <Yuval.Mintz@qlogic.com>. This rework of comments are basically
 related to:
 1) styling of the code,
 2) RSS default Key initiailization related code
 3) redundant code removal

PATCH V4:
This addresses the review comment provided by
Sergei Shtylyov. The changelog of every patch has also
been modified.

PATCH V3:
 Addresses the review comment floated by David Miller

PATCH V2:
1) Bug Fixes and Clean-up: Internally identified
2) Addresses internal review comments by Kenneth Lee and
   by Huang Daode
3) Addresses the review comment from "Yisen.Zhuang(Zhuangyuzeng)"
4) Adds fix from Fengguang Wu for an error generated from
   "kbuild test robot" from Intel
5) Ethtool support for TSO set option from Lisheng

PATCH V1:
Adds initial support of Hip06 SoC with below changes:
This patch-set adds support of new Hisilicon Hip06 SoC to the existing
(already part of net-next) HNS ethernet driver for Hip05 SoC. Hip06 is
a multi-core SoC and is a derivative of Hip05 SoC with lots of new
hardware featres supported like RSS, TSO, hardware VLAN assist etc.

The changes in the driver are mainly due to following:
 1) changes in the DMA descriptor provided by the Hip06 ethernet
    hardware. These changes need to co-exist with already present
    Hip05 DMA descriptor and its operating functions. The decision
    to choose the correct type of DMA descriptor is taken dynamically
    depending upon the version of the hardware (i.e. V1/hip05 or
    V2/hip06, see already existing hisilicon-hns-nic.txt binding file
    for the detailed description version and naming).
 2) To support new features added to the Hip06 ethernet hardware:
    a. RSS (Receive Side Scaling)
    b. TSO (TCP Segment Offload)
    c. Hardware VLAN support (currently we are initializing hardware
       to not assist in stripping the vlan tag at hardware level.
       Proper support of this feature and ethtool would come after
       these patches have been accepted)

Kindly note that, this patchset has been based on latest net-next.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch adds the initializzation code to disable the hardware
vlan support for VLAN Tag stripping by default for now.

Proper support of "hardware VLAN assitance" feature would
soon come in the next coming patches.
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch adds the support of ethtool TSO option to support
Hip06 SoC to HNS
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Signed-off-by: lisheng <lisheng011@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch adds the support of "TSO (TCP Segment Offload)" feature
provided by the Hip06 ethernet hardware to the HNS ethernet
driver.

Enabling this feature would help offload the TCP Segmentation
process to the Hip06 ethernet hardware. This eventually would help
in saving precious cpu cycles.
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Signed-off-by: lisheng <lisheng011@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch adds the support of "RSS (Receive Side Scaling)" feature
provided by the Hip06 ethernet hardware to the HNS ethernet
driver.

This feature helps in distributing the different flows (mapped as
hash by hardware using Toeplitz Hash) to different Queues asssociated
with the processor cores. The mapping of flow-hash values to the
different queues is stored in indirection table (which is per Packet-
parse-Engine/PPE). This patch also provides the changes to re-program
the (flow-hash<->Qid) mapping using the ethtool.
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Reviewed-by: Kenneth Lee <liguozhu@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patchset adds support of Hisilicon Hip06 SoC to the existing HNS
ethernet driver.

The changes in the driver are mainly due to changes in the DMA
descriptor provided by the Hip06 ethernet hardware. These changes
need to co-exist with already present Hip05 DMA descriptor and its
operating functions. The decision to choose the correct type of DMA
descriptor is taken dynamically depending upon the version of the
hardware (i.e. V1/hip05 or V2/hip06, see already existing
hisilicon-hns-nic.txt binding file for detailed description). other
changes includes in SBM, DSAF and PPE modules as well. Changes
affecting the driver related to the newly added ethernet hardware
features in Hip06 would be added as separate patch over this and
subsequent patches.
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Signed-off-by: yankejian <yankejian@huawei.com>
Signed-off-by: huangdaode <huangdaode@hisilicon.com>
Signed-off-by: lipeng <lipeng321@huawei.com>
Signed-off-by: lisheng <lisheng011@huawei.com>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

It is not necessary to use two brackets. As such, the redudant brackets
are removed.

CC: Jay Vosburgh <j.vosburgh@gmail.com>
CC: Veaceslav Falico <vfalico@gmail.com>
CC: Andy Gospodarek <gospo@cumulusnetworks.com>
Signed-off-by: Zhu Yanjun <yanjun.zhu@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Conflicts:
	drivers/net/ethernet/renesas/ravb_main.c
	kernel/bpf/syscall.c
	net/ipv4/ipmr.c

All three conflicts were cases of overlapping changes.
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull networking fixes from David Miller:
 "A lot of Thanksgiving turkey leftovers accumulated, here goes:

   1) Fix bluetooth l2cap_chan object leak, from Johan Hedberg.

   2) IDs for some new iwlwifi chips, from Oren Givon.

   3) Fix rtlwifi lockups on boot, from Larry Finger.

   4) Fix memory leak in fm10k, from Stephen Hemminger.

   5) We have a route leak in the ipv6 tunnel infrastructure, fix from
      Paolo Abeni.

   6) Fix buffer pointer handling in arm64 bpf JIT,f rom Zi Shen Lim.

   7) Wrong lockdep annotations in tcp md5 support, fix from Eric
      Dumazet.

   8) Work around some middle boxes which prevent proper handling of TCP
      Fast Open, from Yuchung Cheng.

   9) TCP repair can do huge kmalloc() requests, build paged SKBs
      instead.  From Eric Dumazet.

  10) Fix msg_controllen overflow in scm_detach_fds, from Daniel
      Borkmann.

  11) Fix device leaks on ipmr table destruction in ipv4 and ipv6, from
      Nikolay Aleksandrov.

  12) Fix use after free in epoll with AF_UNIX sockets, from Rainer
      Weikusat.

  13) Fix double free in VRF code, from Nikolay Aleksandrov.

  14) Fix skb leaks on socket receive queue in tipc, from Ying Xue.

  15) Fix ifup/ifdown crach in xgene driver, from Iyappan Subramanian.

  16) Fix clearing of persistent array maps in bpf, from Daniel
      Borkmann.

  17) In TCP, for the cross-SYN case, we don't initialize tp->copied_seq
      early enough.  From Eric Dumazet.

  18) Fix out of bounds accesses in bpf array implementation when
      updating elements, from Daniel Borkmann.

  19) Fill gaps in RCU protection of np->opt in ipv6 stack, from Eric
      Dumazet.

  20) When dumping proxy neigh entries, we have to accomodate NULL
      device pointers properly, from Konstantin Khlebnikov.

  21) SCTP doesn't release all ipv6 socket resources properly, fix from
      Eric Dumazet.

  22) Prevent underflows of sch->q.qlen for multiqueue packet
      schedulers, also from Eric Dumazet.

  23) Fix MAC and unicast list handling in bnxt_en driver, from Jeffrey
      Huang and Michael Chan.

  24) Don't actively scan radar channels, from Antonio Quartulli"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (110 commits)
  net: phy: reset only targeted phy
  bnxt_en: Setup uc_list mac filters after resetting the chip.
  bnxt_en: enforce proper storing of MAC address
  bnxt_en: Fixed incorrect implementation of ndo_set_mac_address
  net: lpc_eth: remove irq > NR_IRQS check from probe()
  net_sched: fix qdisc_tree_decrease_qlen() races
  openvswitch: fix hangup on vxlan/gre/geneve device deletion
  ipv4: igmp: Allow removing groups from a removed interface
  ipv6: sctp: implement sctp_v6_destroy_sock()
  arm64: bpf: add 'store immediate' instruction
  ipv6: kill sk_dst_lock
  ipv6: sctp: add rcu protection around np->opt
  net/neighbour: fix crash at dumping device-agnostic proxy entries
  sctp: use GFP_USER for user-controlled kmalloc
  sctp: convert sack_needed and sack_generation to bits
  ipv6: add complete rcu protection around np->opt
  bpf: fix allocation warnings in bpf maps and integer overflow
  mvebu: dts: enable IP checksum with jumbo frames for Armada 38x on Port0
  net: mvneta: enable setting custom TX IP checksum limit
  net: mvneta: fix error path for building skb
  ...

Pull block fixes from Jens Axboe:
 "A collection of fixes from this series.  The most important here is a
  regression fix for an issue that some folks would hit in blk-merge.c,
  and the NVMe queue depth limit for the screwed up Apple "nvme"
  controller.

  In more detail, this pull request contains:

   - a set of fixes for null_blk, including a fix for a few corner cases
     where we could hang the device.  From Arianna and Paolo.

   - lightnvm:
        - A build improvement from Keith.
        - Update the qemu pci id detection from Matias.
        - Error handling fixes for leaks and other little fixes from
          Sudip and Wenwei.

   - fix from Eric where BLKRRPART would not return EBUSY for whole
     device mounts, only when partitions were mounted.

   - fix from Jan Kara, where EOF O_DIRECT reads would return
     negatively.

   - remove check for rq_mergeable() when checking limits for cloned
     requests.  The check doesn't make any sense.  It's assuming that
     since NOMERGE is set on the request that we don't have to
     recalculate limits since the request didn't change, but that's not
     true if the request has been redirected.  From Hannes.

   - correctly get the bio front segment value set for single segment
     bio's, fixing a BUG() in blk-merge.  From Ming"

* 'for-linus' of git://git.kernel.dk/linux-block:
  nvme: temporary fix for Apple controller reset
  null_blk: change type of completion_nsec to unsigned long
  null_blk: guarantee device restart in all irq modes
  null_blk: set a separate timer for each command
  blk-merge: fix computing bio->bi_seg_front_size in case of single segment
  direct-io: Fix negative return from dio read beyond eof
  block: Always check queue limits for cloned requests
  lightnvm: missing nvm_lock acquire
  lightnvm: unconverted ppa returned in get_bb_tbl
  lightnvm: refactor and change vendor id for qemu
  lightnvm: do device max sectors boundary check first
  lightnvm: fix ioctl memory leaks
  lightnvm: free memory when gennvm register fails
  lightnvm: Simplify config when disabled
  Return EBUSY from BLKRRPART for mounted whole-dev fs

Pull tracing fix from Steven Rostedt:
 "During the merge window I added a new file that is used to filter
  trace events on pids.  It filters all events where only tasks with
  their pid in that file exists.  It also handles the sched_switch and
  sched_wakeup trace events where the current task does not have its pid
  in the file, but the task either being switched to or awaken does.

  Unfortunately, I forgot about sched_wakeup_new and sched_waking.  Both
  of these tracepoints use the same class as the sched_wakeup
  tracepoint, and they too should be included in what gets filtered by
  the set_event_pid file"

* tag 'trace-v4.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Add sched_wakeup_new and sched_waking tracepoints for pid filter

Merge tag 'mac80211-for-davem-2015-12-02' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211

Johannes Berg says:

====================
A small set of fixes for 4.4:
 * fix scanning in mac80211 to not actively scan radar
   channels (from Antonio)
 * fix uninitialized variable in remain-on-channel that
   could lead to treating frame TX as remain-on-channel
   and not sending the frame at all
 * remove NL80211_FEATURE_FULL_AP_CLIENT_STATE again, it
   was broken and needs more work, we'll enable it later
 * fix call_rcu() induced use-after-reset/free in mesh
   (that was suddenly causing issues in certain tests)
 * always request block-ack window size 64 as we found
   some APs will otherwise crash (really ...)
 * fix P2P-Device teardown sequence to avoid restarting
   with uninitialized data
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Better to just warn the user that something really odd is going on and
continue to run.
Suggested-by: Or Gerlitz <gerlitz.or@gmail.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

It is possible to address another chip on same MDIO bus. The case is
correctly handled for media advertising. It is taken into account
only if mii_data->phy_id == phydev->addr. However, this condition
was missing for reset case.
Signed-off-by: Jérôme Pouiller <jezz@sysmic.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Typically we return error pointers when we want to use those
pointers in the non-error case, but this function is just
returning error pointers or NULL for success. Change the style to
plain int to follow normal kernel coding styles.

Cc: Joachim Eastwood <manabian@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Commit 5405ff6e ("tipc: convert node lock to rwlock")
introduced a bug to the node reference counter handling. When a
message is successfully sent in the function tipc_node_xmit(),
we return directly after releasing the node lock, instead of
continuing and decrementing the node reference counter as we
should do.

This commit fixes this bug.
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Stas Sergeev says:

====================
mvneta: implement ethtool autonegotiation control

These 2 patches add an ability to control the
autonegotiation via ethtool. For example:

ethtool -s eth0 autoneg off
ethtool -s eth0 autoneg on

This is needed if you want to connect the mvneta's MII
to different switches or PHYs: the ones the do support
the in-band status, and the ones that do not.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch allows to do
ethtool -s eth0 autoneg off
ethtool -s eth0 autoneg on
to disable or enable autonegotiation at run-time.
Without that functionality, the only way to control the autonegotiation
is to modify the device tree.

This is needed if you plan to use the same kernel with
different ethernet switches, the ones that support the in-band
status and the ones that not.

CC: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
CC: netdev@vger.kernel.org
CC: linux-kernel@vger.kernel.org
Signed-off-by: Stas Sergeev <stsp@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

This moves autoneg-related bit manipulations to the single place.

CC: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
CC: netdev@vger.kernel.org
CC: linux-kernel@vger.kernel.org
Signed-off-by: Stas Sergeev <stsp@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

These new helpers simplify implementing multi-driver modules and
properly handle failure to register one driver by unregistering all
previously registered drivers.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

These new helpers simplify implementing multi-driver modules and
properly handle failure to register one driver by unregistering all
previously registered drivers.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

These new helpers simplify implementing multi-driver modules and
properly handle failure to register one driver by unregistering all
previously registered drivers.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

These new helpers simplify implementing multi-driver modules and
properly handle failure to register one driver by unregistering all
previously registered drivers.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

* Register PF_PPPOX with pppox module rather than with pppoe,
    so that pppoe doesn't get loaded for any PF_PPPOX socket.

  * Register PX_PROTO_* with standard MODULE_ALIAS_NET_PF_PROTO()
    instead of using pppox's own naming scheme.

  * While there, add auto-loading feature for pptp.
Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>

Michael Chan says:

====================
bnxt_en: set mac address and uc_list bug fixes.

Fix ndo_set_mac_address() for PF and VF.
Re-apply uc_list after chip reset.

v2: Fix compile error if CONFIG_BNXT_SRIOV is not set.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Call bnxt_cfg_rx_mode() in bnxt_init_chip() to setup uc_list and
mc_list mac address filters.  Before the patch, uc_list is not
setup again after chip reset (such as ethtool ring size change)
and macvlans don't work any more after that.

Modify bnxt_cfg_rx_mode() to return error codes appropriately so
that the init chip sequence can detect any failures.
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

For PF, the bp->pf.mac_addr always holds the permanent MAC
addr assigned by the HW.  For VF, the bp->vf.mac_addr always
holds the administrator assigned VF MAC addr. The random
generated VF MAC addr should never get stored to bp->vf.mac_addr.
This way, when the VF wants to change the MAC address, we can tell
if the adminstrator has already set it and disallow the VF from
changing it.

v2: Fix compile error if CONFIG_BNXT_SRIOV is not set.
Signed-off-by: Jeffrey Huang <huangjw@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The existing ndo_set_mac_address only copies the new MAC addr
and didn't set the new MAC addr to the HW. The correct way is
to delete the existing default MAC filter from HW and add
the new one. Because of RFS filters are also dependent on the
default mac filter l2 context, the driver must go thru
close_nic() to delete the default MAC and RFS filters, then
open_nic() to set the default MAC address to HW.
Signed-off-by: Jeffrey Huang <huangjw@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Stefan Hajnoczi says:

====================
Add virtio transport for AF_VSOCK

v2:
 * Rebased onto Linux v4.4-rc2
 * vhost: Refuse to assign reserved CIDs
 * vhost: Refuse guest CID if already in use
 * vhost: Only accept correctly addressed packets (no spoofing!)
 * vhost: Support flexible rx/tx descriptor layout
 * vhost: Add missing total_tx_buf decrement
 * virtio_transport: Fix total_tx_buf accounting
 * virtio_transport: Add virtio_transport global mutex to prevent races
 * common: Notify other side of SOCK_STREAM disconnect (fixes shutdown
   semantics)
 * common: Avoid recursive mutex_lock(tx_lock) for write_space (fixes deadlock)
 * common: Define VIRTIO_VSOCK_TYPE_STREAM/DGRAM hardware interface constants
 * common: Define VIRTIO_VSOCK_SHUTDOWN_RCV/SEND hardware interface constants
 * common: Fix peer_buf_alloc inheritance on child socket

This patch series adds a virtio transport for AF_VSOCK (net/vmw_vsock/).
AF_VSOCK is designed for communication between virtual machines and
hypervisors.  It is currently only implemented for VMware's VMCI transport.

This series implements the proposed virtio-vsock device specification from
here:
http://comments.gmane.org/gmane.comp.emulators.virtio.devel/855

Most of the work was done by Asias He and Gerd Hoffmann a while back.  I have
picked up the series again.

The QEMU userspace changes are here:
https://github.com/stefanha/qemu/commits/vsock

Why virtio-vsock?
-----------------
Guest<->host communication is currently done over the virtio-serial device.
This makes it hard to port sockets API-based applications and is limited to
static ports.

virtio-vsock uses the sockets API so that applications can rely on familiar
SOCK_STREAM and SOCK_DGRAM semantics.  Applications on the host can easily
connect to guest agents because the sockets API allows multiple connections to
a listen socket (unlike virtio-serial).  This simplifies the guest<->host
communication and eliminates the need for extra processes on the host to
arbitrate virtio-serial ports.

Overview
--------
This series adds 3 pieces:

1. virtio_transport_common.ko - core virtio vsock code that uses vsock.ko

2. virtio_transport.ko - guest driver

3. drivers/vhost/vsock.ko - host driver

Howto
-----
The following kernel options are needed:
  CONFIG_VSOCKETS=y
  CONFIG_VIRTIO_VSOCKETS=y
  CONFIG_VIRTIO_VSOCKETS_COMMON=y
  CONFIG_VHOST_VSOCK=m

Launch QEMU as follows:
  # qemu ... -device vhost-vsock-pci,id=vhost-vsock-pci0,guest-cid=3

Guest and host can communicate via AF_VSOCK sockets.  The host's CID (address)
is 2 and the guest is automatically assigned a CID (use VMADDR_CID_ANY (-1) to
bind to it).

Status
------
There are a few design changes I'd like to make to the virtio-vsock device:

1. The 3-way handshake isn't necessary over a reliable transport (virtqueue).
   Spoofing packets is also impossible so the security aspects of the 3-way
   handshake (including syn cookie) add nothing.  The next version will have a
   single operation to establish a connection.

2. Credit-based flow control doesn't work for SOCK_DGRAM since multiple clients
   can transmit to the same listen socket.  There is no way for the clients to
   coordinate buffer space with each other fairly.  The next version will drop
   credit-based flow control for SOCK_DGRAM and only rely on best-effort
   delivery.  SOCK_STREAM still has guaranteed delivery.

3. In the next version only the host will be able to establish connections
   (i.e. to connect to a guest agent).  This is for security reasons since
   there is currently no ability to provide host services only to certain
   guests.  This also matches how AF_VSOCK works on modern VMware hypervisors.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Enable virtio-vsock and vhost-vsock.
Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

VM sockets vhost transport implementation. This module runs in host
kernel.
Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

VM sockets virtio transport implementation. This module runs in guest
kernel.
Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This module contains the common code and header files for the following
virtio-vsock and virtio-vhost kernel modules.
Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>