Add kernel-doc documentation for phylink kernel APIs, and link it into
the networking kapi documentation under "Network device support".
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Restart 802.3z negotiation when the net device is brought up to ensure
that the link partner has our current link modes.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

phylink_init_eee() serves no purpose, remove it.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add support for handling the faster 2.5G and 10G link modes when used
with SFP modules.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Since the handling of SGMII and 802.3z is now the same, combine the
MLO_AN_xxx constants into a single MLO_AN_INBAND, and use the PHY
interface mode to distinguish between Cisco SGMII and 802.3z.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The code handling SGMII and 802.3z is essentially the same, except that
we assume 802.3z has no PHY.  Re-organise the code such that these cases
are merged, and exclude 802.3z mode from having a PHY attached.  This
results in the same link handling behaviour as before.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add and use phy_interface_mode_is_8023z() helper to identify the
interface modes that use 802.3z negotiation.  Use it in phylink's
phylink_mac_an_restart().
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Incorrect/missing annotations caused a few sparse warnings:

rtnetlink.c:155:15: incompatible types .. (different address spaces)
rtnetlink.c:157:23: incompatible types .. (different address spaces)
rtnetlink.c:185:15: incompatible types .. (different address spaces)
rtnetlink.c:285:15: incompatible types .. (different address spaces)
rtnetlink.c:317:9: incompatible types .. (different address spaces)
rtnetlink.c:3054:23: incompatible types .. (different address spaces)

no change in generated code.

Fixes: addf9b90 ("net: rtnetlink: use rcu to free rtnl message handlers")
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

Small overlapping change conflict ('net' changed a line,
'net-next' added a line right afterwards) in flexcan.c
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull virtio fixes from Michael Tsirkin:
 "virtio and qemu bugfixes

  A couple of bugfixes that just became ready"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio_balloon: fix increment of vb->num_pfns in fill_balloon()
  virtio: release virtio index when fail to device_register
  fw_cfg: fix driver remove

Pull networking fixes from David Miller:

 1) Various TCP control block fixes, including one that crashes with
    SELinux, from David Ahern and Eric Dumazet.

 2) Fix ACK generation in rxrpc, from David Howells.

 3) ipvlan doesn't set the mark properly in the ipv4 route lookup key,
    from Gao Feng.

 4) SIT configuration doesn't take on the frag_off ipv4 field
    configuration properly, fix from Hangbin Liu.

 5) TSO can fail after device down/up on stmmac, fix from Lars Persson.

 6) Various bpftool fixes (mostly in JSON handling) from Quentin Monnet.

 7) Various SKB leak fixes in vhost/tun/tap (mostly observed as
    performance problems). From Wei Xu.

 8) mvpps's TX descriptors were not zero initialized, from Yan Markman.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (57 commits)
  tcp: use IPCB instead of TCP_SKB_CB in inet_exact_dif_match()
  tcp: add tcp_v4_fill_cb()/tcp_v4_restore_cb()
  rxrpc: Fix the MAINTAINERS record
  rxrpc: Use correct netns source in rxrpc_release_sock()
  liquidio: fix incorrect indentation of assignment statement
  stmmac: reset last TSO segment size after device open
  ipvlan: Add the skb->mark as flow4's member to lookup route
  s390/qeth: build max size GSO skbs on L2 devices
  s390/qeth: fix GSO throughput regression
  s390/qeth: fix thinko in IPv4 multicast address tracking
  tap: free skb if flags error
  tun: free skb in early errors
  vhost: fix skb leak in handle_rx()
  bnxt_en: Fix a variable scoping in bnxt_hwrm_do_send_msg()
  bnxt_en: fix dst/src fid for vxlan encap/decap actions
  bnxt_en: wildcard smac while creating tunnel decap filter
  bnxt_en: Need to unconditionally shut down RoCE in bnxt_shutdown
  phylink: ensure we take the link down when phylink_stop() is called
  sfp: warn about modules requiring address change sequence
  sfp: improve RX_LOS handling
  ...

The chip family of TILEPro and TILE-Gx was developed by Tilera, which
was eventually acquired by Mellanox.  The tile architecture was added to
the kernel in 2010 and first appeared in 2.6.36.

Now at Mellanox we are developing new chips based on the ARM64
architecture; our last TILE-Gx chip (the Gx72) was released in 2013, and
our customers using tile architecture products are not, as far as we
know, looking to upgrade to newer kernel releases.  In the absence of
someone in the community stepping up to take over maintainership, this
commit marks the architecture as orphaned.

Cc: Chris Metcalf <metcalf@alum.mit.edu>
Signed-off-by: Chris Metcalf <cmetcalf@mellanox.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

convert remaining users of rtnl_register to rtnl_register_module
and un-export rtnl_register.
Requested-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

Merge tag 'linux-can-next-for-4.16-20171201' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next

Marc Kleine-Budde says:

====================
pull-request: can-next 2017-12-01

this is a pull request of 10 patches for net-next/master.

The first two patches are by Arnd Bergmann, they convert the peak_usb
from using "struct timeval" to "ktime_t". The error handling in the
vxcan driver is clean up by Markus Elfring's patch. Bhumika Goyal
contributes a patch for the c_can_pci driver to make the pci data const.
The six patches by Pankaj Bansal for the flexcan driver add LS1021A
support by making the endianness of the driver configurable by the
device tree.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Daniel Borkmann says:

====================
pull-request: bpf-next 2017-12-03

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) Addition of a software model for BPF offloads in order to ease
   testing code changes in that area and make semantics more clear.
   This is implemented in a new driver called netdevsim, which can
   later also be extended for other offloads. SR-IOV support is added
   as well to netdevsim. BPF kernel selftests for offloading are
   added so we can track basic functionality as well as exercising
   all corner cases around BPF offloading, from Jakub.

2) Today drivers have to drop the reference on BPF progs they hold
   due to XDP on device teardown themselves. Change this in order
   to make XDP handling inside the drivers less error prone, and
   move disabling XDP to the core instead, also from Jakub.

3) Misc set of BPF verifier improvements and cleanups as preparatory
   work for upcoming BPF-to-BPF calls. Among others, this set also
   improves liveness marking such that pruning can be slightly more
   effective. Register and stack liveness information is now included
   in the verifier log as well, from Alexei.

4) nfp JIT improvements in order to identify load/store sequences in
   the BPF prog e.g. coming from memcpy lowering and optimizing them
   through the NPU's command push pull (CPP) instruction, from Jiong.

5) Cleanups to test_cgrp2_attach2.c BPF sample code in oder to remove
   bpf_prog_attach() magic values and replacing them with actual proper
   attach flag instead, from David.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Florian Westphal says:

====================
rtnetlink: rework handler (un)registering

Peter Zijlstra reported (referring to commit 019a3169,
"rtnetlink: add reference counting to prevent module unload while dump is in progress"):

 1) it not in fact a refcount, so using refcount_t is silly
 2) there is a distinct lack of memory barriers, so we can easily
    observe the decrement while the msg_handler is still in progress.
 3) waiting with a schedule()/yield() loop is complete crap and subject
    life-locks, imagine doing that rtnl_unregister_all() from a RT task.

In ancient times rtnetlink exposed a statically-sized table with
preset doit/dumpit handlers to be called for a protocol/type pair.

Later the rtnl_register interface was added and the table was allocated
on demand.  Eventually these were also used by modules.

Problem is that nothing prevents module unload while a netlink dump
is in progress.  netlink dumps can be span multiple recv calls and
netlink core saves the to-be-repeated dumper address for later invocation.

To prevent rmmod the netlink core expects callers to pass in the owning
module so a reference can be taken.

So far rtnetlink wasn't doing this, add new interface to pass THIS_MODULE.
Moreover, when converting parts of the rtnetlink handling to rcu this code
gained way too many READ_ONCE spots, remove them and the extra refcounting.

Take a module reference when running dumpit and doit callbacks
and never alter content of rtnl_link structures after they have been
published via rcu_assign_pointer.

Based partially on earlier patch from Peter.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

This removes __rtnl_register and switches callers to either
rtnl_register or rtnl_register_module.

Also, rtnl_register() will now print an error if memory allocation
failed rather than panic the kernel.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

all of these can be compiled as a module, so use new
_module version to make sure module can no longer be removed
while callback/dump is in use.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add yet another rtnl_register function.  It will be used by modules
that can be removed.

The passed module struct is used to prevent module unload while
a netlink dump is in progress or when a DOIT_UNLOCKED doit callback
is called.

Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtnetlink is littered with READ_ONCE() because we can have read accesses
while another cpu can write to the structure we're reading by
(un)registering doit or dumpit handlers.

This patch changes this so that (un)registering cpu allocates a new
structure and then publishes it via rcu_assign_pointer, i.e. once
another cpu can see such pointer no modifications will occur anymore.

based on initial patch from Peter Zijlstra.

Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

Previous patch mistakenly removed three chip-specific config settings.
Add them again.

Fixes: 80274aba "net: phy: remove generic settings for callbacks config_aneg and read_status from drivers"
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

William Tu says:

====================
add ip6 gre and gretap collect_md mode

Similar to gre, vxlan, geneve, ipip tunnels, allow ip6gretap tunnels to
operate in collect metadata mode.  The first patch adds the support to
ip6_gre.c. The second patch enables unsetting the csum for ipv6 tunnel,
when using bpf_skb_[gs]et_tunnel_key() helpers.  Finally, the last patch
adds the ip6 gre and gretap tunnel test cases to BPF sample code.

The corresponding iproute2 patch:
https://marc.info/?l=linux-netdev&m=151216943128087&w=2
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Extend existing tests for vxlan, gre, geneve, ipip, erspan,
to include ip6 gre and gretap tunnel.
Signed-off-by: William Tu <u9012063@gmail.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Before the patch, BPF_F_ZERO_CSUM_TX can be used only for ipv4 tunnel.
With introduction of ip6gretap collect_md mode, the flag should be also
supported for ipv6.
Signed-off-by: William Tu <u9012063@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

Similar to gre, vxlan, geneve, ipip tunnels, allow ip6 gre and gretap
tunnels to operate in collect metadata mode.  bpf_skb_[gs]et_tunnel_key()
helpers can make use of it right away.  OVS can use it as well in the
future.
Signed-off-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

If state is not PHY_HALTED I see no need to temporarily disable
interrupts on the device. As long as the current interrupt isn't acked
on the device no new interrupt can happen anyway.

In addition remove a unneeded enabling of interrupts in the state
machine when handling state PHY_CHANGELINK.

Tested on a Odroid-C2 with RTL8211F phy in interrupt mode.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

After commits c974bdbc "net: phy: Use threaded IRQ, to allow IRQ from
sleeping devices" and 664fcf12 "net: phy: Threaded interrupts allow
some simplification" all relevant code pieces run in process context
anyway and I don't think we need the disabling of interrupts any longer.

Interestingly enough, latter commit already removed the comment
explaining why interrupts need to be temporarily disabled.

On my system phy interrupt mode works fine with this patch.
However I may miss something, especially in the context of shared phy
interrupts, therefore I'd appreciate if more people could test this.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Daniel Borkmann says:

====================
pull-request: bpf 2017-12-02

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) Fix a compilation warning in xdp redirect tracepoint due to
   missing bpf.h include that pulls in struct bpf_map, from Xie.

2) Limit the maximum number of attachable BPF progs for a given
   perf event as long as uabi is not frozen yet. The hard upper
   limit is now 64 and therefore the same as with BPF multi-prog
   for cgroups. Also add related error checking for the sample
   BPF loader when enabling and attaching to the perf event, from
   Yonghong.

3) Specifically set the RLIMIT_MEMLOCK for the test_verifier_log
   case, so that the test case can always pass and not fail in
   some environments due to too low default limit, also from
   Yonghong.

4) Fix up a missing license header comment for kernel/bpf/offload.c,
   from Jakub.

5) Several fixes for bpftool, among others a crash on incorrect
   arguments when json output is used, error message handling
   fixes on unknown options and proper destruction of json writer
   for some exit cases, all from Quentin.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Eric Dumazet says:

====================
tcp: add tcp_v4_fill_cb()/tcp_v4_restore_cb()

James Morris reported kernel stack corruption bug that
we tracked back to commit 971f10ec ("tcp: better TCP_SKB_CB
layout to reduce cache line misses")

First patch needs to be backported to kernels >= 3.18,
while second patch needs to be backported to kernels >= 4.9, since
this was the time when inet_exact_dif_match appeared.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

After this fix : ("tcp: add tcp_v4_fill_cb()/tcp_v4_restore_cb()"),
socket lookups happen while skb->cb[] has not been mangled yet by TCP.

Fixes: a04a480d ("net: Require exact match for TCP socket lookups if dif is l3mdev")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

James Morris reported kernel stack corruption bug [1] while
running the SELinux testsuite, and bisected to a recent
commit bffa72cf ("net: sk_buff rbnode reorg")

We believe this commit is fine, but exposes an older bug.

SELinux code runs from tcp_filter() and might send an ICMP,
expecting IP options to be found in skb->cb[] using regular IPCB placement.

We need to defer TCP mangling of skb->cb[] after tcp_filter() calls.

This patch adds tcp_v4_fill_cb()/tcp_v4_restore_cb() in a very
similar way we added them for IPv6.

[1]
[  339.806024] SELinux: failure in selinux_parse_skb(), unable to parse packet
[  339.822505] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: ffffffff81745af5
[  339.822505]
[  339.852250] CPU: 4 PID: 3642 Comm: client Not tainted 4.15.0-rc1-test #15
[  339.868498] Hardware name: LENOVO 10FGS0VA1L/30BC, BIOS FWKT68A   01/19/2017
[  339.885060] Call Trace:
[  339.896875]  <IRQ>
[  339.908103]  dump_stack+0x63/0x87
[  339.920645]  panic+0xe8/0x248
[  339.932668]  ? ip_push_pending_frames+0x33/0x40
[  339.946328]  ? icmp_send+0x525/0x530
[  339.958861]  ? kfree_skbmem+0x60/0x70
[  339.971431]  __stack_chk_fail+0x1b/0x20
[  339.984049]  icmp_send+0x525/0x530
[  339.996205]  ? netlbl_skbuff_err+0x36/0x40
[  340.008997]  ? selinux_netlbl_err+0x11/0x20
[  340.021816]  ? selinux_socket_sock_rcv_skb+0x211/0x230
[  340.035529]  ? security_sock_rcv_skb+0x3b/0x50
[  340.048471]  ? sk_filter_trim_cap+0x44/0x1c0
[  340.061246]  ? tcp_v4_inbound_md5_hash+0x69/0x1b0
[  340.074562]  ? tcp_filter+0x2c/0x40
[  340.086400]  ? tcp_v4_rcv+0x820/0xa20
[  340.098329]  ? ip_local_deliver_finish+0x71/0x1a0
[  340.111279]  ? ip_local_deliver+0x6f/0xe0
[  340.123535]  ? ip_rcv_finish+0x3a0/0x3a0
[  340.135523]  ? ip_rcv_finish+0xdb/0x3a0
[  340.147442]  ? ip_rcv+0x27c/0x3c0
[  340.158668]  ? inet_del_offload+0x40/0x40
[  340.170580]  ? __netif_receive_skb_core+0x4ac/0x900
[  340.183285]  ? rcu_accelerate_cbs+0x5b/0x80
[  340.195282]  ? __netif_receive_skb+0x18/0x60
[  340.207288]  ? process_backlog+0x95/0x140
[  340.218948]  ? net_rx_action+0x26c/0x3b0
[  340.230416]  ? __do_softirq+0xc9/0x26a
[  340.241625]  ? do_softirq_own_stack+0x2a/0x40
[  340.253368]  </IRQ>
[  340.262673]  ? do_softirq+0x50/0x60
[  340.273450]  ? __local_bh_enable_ip+0x57/0x60
[  340.285045]  ? ip_finish_output2+0x175/0x350
[  340.296403]  ? ip_finish_output+0x127/0x1d0
[  340.307665]  ? nf_hook_slow+0x3c/0xb0
[  340.318230]  ? ip_output+0x72/0xe0
[  340.328524]  ? ip_fragment.constprop.54+0x80/0x80
[  340.340070]  ? ip_local_out+0x35/0x40
[  340.350497]  ? ip_queue_xmit+0x15c/0x3f0
[  340.361060]  ? __kmalloc_reserve.isra.40+0x31/0x90
[  340.372484]  ? __skb_clone+0x2e/0x130
[  340.382633]  ? tcp_transmit_skb+0x558/0xa10
[  340.393262]  ? tcp_connect+0x938/0xad0
[  340.403370]  ? ktime_get_with_offset+0x4c/0xb0
[  340.414206]  ? tcp_v4_connect+0x457/0x4e0
[  340.424471]  ? __inet_stream_connect+0xb3/0x300
[  340.435195]  ? inet_stream_connect+0x3b/0x60
[  340.445607]  ? SYSC_connect+0xd9/0x110
[  340.455455]  ? __audit_syscall_entry+0xaf/0x100
[  340.466112]  ? syscall_trace_enter+0x1d0/0x2b0
[  340.476636]  ? __audit_syscall_exit+0x209/0x290
[  340.487151]  ? SyS_connect+0xe/0x10
[  340.496453]  ? do_syscall_64+0x67/0x1b0
[  340.506078]  ? entry_SYSCALL64_slow_path+0x25/0x25

Fixes: 971f10ec ("tcp: better TCP_SKB_CB layout to reduce cache line misses")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: James Morris <james.l.morris@oracle.com>
Tested-by: James Morris <james.l.morris@oracle.com>
Tested-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull ARM fix from Russell King:
 "Just one fix this time around, for the late commit in the merge window
  that triggered a problem with qemu. Qemu is apparently also going to
  receive a fix for the discovered issue"

* 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm:
  ARM: avoid faulting on qemu

Pull i2c fixes from Wolfram Sang:
 "Here are two bugfixes for I2C, fixing a memleak in the core and irq
  allocation for i801.

  Also three bugfixes for the at24 eeprom driver which Bartosz collected
  while taking over maintainership for this driver"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  eeprom: at24: check at24_read/write arguments
  eeprom: at24: fix reading from 24MAC402/24MAC602
  eeprom: at24: correctly set the size for at24mac402
  i2c: i2c-boardinfo: fix memory leaks on devinfo
  i2c: i801: Fix Failed to allocate irq -2147483648 error

Merge tag 'hwmon-for-linus-v4.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull hwmon fixes from Guenter Roeck:
 "Fixes:

   - Drop reference to obsolete maintainer tree

   - Fix overflow bug in pmbus driver

   - Fix SMBUS timeout problem in jc42 driver

  For the SMBUS timeout handling, we had a brief discussion if this
  should be considered a bug fix or a feature. Peter says "it fixes real
  problems where the application misbehave due to faulty content when
  reading from an eeprom", and he needs the patch in his company's v4.14
  images. This is good enough for me and warrants backport to stable
  kernels"

* tag 'hwmon-for-linus-v4.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (jc42) optionally try to disable the SMBUS timeout
  hwmon: (pmbus) Use 64bit math for DIRECT format values
  hwmon: Drop reference to Jean's tree

Martin KaFai Lau says:

====================
tcp: Add a 2nd listener hashtable (port+addr)

This patch set adds a 2nd listener hashtable.  It is to resolve
the performance issue when a process is listening at many IP
addresses with the same port (e.g. [IP1]:443, [IP2]:443... [IPN]:443)

v2:
- Move the new lhash2 and lhash2_mask before the existing
  listening_hash to avoid adding another cacheline
  to inet_hashinfo (Suggested by Eric Dumazet, Thanks!)
- I take this chance to plug an existing 4 bytes hole while
  adding 'unsigned int lhash2_mask'.
- Add some comments about lhash2 in inet_hashtables.h
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Enable the second listener hashtable in TCP.
The scale is the same as UDP which is one slot per 2MB.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The current listener hashtable is hashed by port only.
When a process is listening at many IP addresses with the same port (e.g.
[IP1]:443, [IP2]:443... [IPN]:443), the inet[6]_lookup_listener()
performance is degraded to a link list.  It is prone to syn attack.

UDP had a similar issue and a second hashtable was added to resolve it.

This patch adds a second hashtable for the listener's sockets.
The second hashtable is hashed by port and address.

It cannot reuse the existing skc_portaddr_node which is shared
with skc_bind_node.  TCP listener needs to use skc_bind_node.
Instead, this patch adds a hlist_node 'icsk_listen_portaddr_node' to
the inet_connection_sock which the listener (like TCP) also belongs to.

The new portaddr hashtable may need two lookup (First by IP:PORT.
Second by INADDR_ANY:PORT if the IP:PORT is a not found).   Hence,
it implements a similar cut off as UDP such that it will only consult the
new portaddr hashtable if the current port-only hashtable has >10
sk in the link-list.

lhash2 and lhash2_mask are added to 'struct inet_hashinfo'.  I take
this chance to plug a 4 bytes hole.  It is done by first moving
the existing bind_bucket_cachep up and then add the new
(int lhash2_mask, *lhash2) after the existing bhash_size.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch moves the udp[46]_portaddr_hash()
to net/ip[v6].h.  The function name is renamed to
ipv[46]_portaddr_hash().

It will be used by a later patch which adds a second listener
hashtable hashed by the address and port.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch adds a count to the 'struct inet_listen_hashbucket'.
It counts how many sk is hashed to a bucket.  It will be
used to decide if the (to-be-added) portaddr listener's hashtable
should be used during inet[6]_lookup_listener().
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>