No need to carry this reference in stmmac_pci_info - the Quark-specific
setup handler knows that it needs to use the Quark-specific DMI table.
This also allows to drop the stmmac_pci_info reference from the setup
handler parameter list.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Move the special case for the early Galileo firmware into
quark_default_setup. This allows to use stmmac_pci_find_phy_addr for
non-quark cases.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Make stmmac_default_data compatible with stmmac_pci_info.setup and use
an info structure for all devices. This allows to make the probing more
regular.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

By removing the PCI device reference from the structure and passing it
as parameters to the interested functions, we can make quark_pci_info
const.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When the VF NIC is opened, the synthetic NIC's carrier state is set to
off. This tells the host to transitions data path to the VF device. But
if startup script or user manipulates the admin state of the netvsc
device directly for example:
        # ifconfig eth0 down
	# ifconfig eth0 up
Then the carrier state of the synthetic NIC would be on, even though the
data path was still over the VF NIC. This patch sets the carrier state
of synthetic NIC with consideration of the related VF state.
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

We simply use rndis_device->link_state in the netdev_dbg. The variable,
link_state from struct netvsc_device_info, is not used anywhere else.
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tracex5_kern.c build failed with the following error message:
  ../samples/bpf/tracex5_kern.c:12:10: fatal error: 'syscall_nrs.h' file not found
  #include "syscall_nrs.h"
The generated file syscall_nrs.h is put in build/samples/bpf directory,
but this directory is not in include path, hence build failed.

The fix is to add $(obj) into the clang compilation path.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Sowmini Varadhan says:

====================
rds: tcp: fixes

Patch1 is a bug fix for correct reconnect when a connection
is restarted. Patch 2 accelerates cleanup by setting linger
to 1 and sending a RST to the peer.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

If we are unloading the rds_tcp module, we can set linger to 1
and drop pending packets to accelerate reconnect. The peer will
end up resetting the connection based on new generation numbers
of the new incarnation, so hanging on to unsent TCP packets via
linger is mostly pointless in this case.
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Tested-by: Jenny Xu <jenny.x.xu@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The RDS handshake ping probe added by commit 5916e2c1
("RDS: TCP: Enable multipath RDS for TCP") is sent from rds_sendmsg()
before the first data packet is sent to a peer. If the conversation
is not bidirectional  (i.e., one side is always passive and never
invokes rds_sendmsg()) and the passive side restarts its rds_tcp
module, a new HS ping probe needs to be sent, so that the number
of paths can be re-established.

This patch achieves that by sending a HS ping probe from
rds_tcp_accept_one() when c_npaths is 0 (i.e., we have not done
a handshake probe with this peer yet).
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Tested-by: Jenny Xu <jenny.x.xu@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The update to ibmvnic_init to allow an EAGAIN return code broke
the calling of ibmvnic_init from ibmvnic_probe. The code now
will return from this point in the probe routine if anything
other than EAGAIN is returned. The check should be to see if rc
is non-zero and not equal to EAGAIN.

Without this fix, the vNIC driver can return 0 (success) from
its probe routine due to ibmvnic_init returning zero, but before
completing the probe process and registering with the netdev layer.

Fixes: 6a2fb0e9 (ibmvnic: driver initialization for kdump/kexec)
Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Thomas Falcon says:

====================
ibmvnic: Correct long-term-mapped buffer error handling

This patch set fixes the error-handling of long-term-mapped buffers
during adapter initialization and reset. The first patch fixes a bug
in an incorrectly defined descriptor that was keeping the return
codes from the VIO server from being properly checked. The second patch
fixes and cleans up the error-handling implementation.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

The patch stores the return code of the REQUEST_MAP_RSP sub-CRQ command
in the private data structure, where it can be later checked during
device open or a reset.

In the case of a reset, the mapping request to the vNIC Server may fail,
especially in the case of a partition migration. The driver attempts to
handle this by re-allocating the buffer and re-sending the mapping request.

The original error handling implementation was removed. The separate
function handling the REQUEST_MAP response message was also removed,
since it is now simple enough to be handled in the ibmvnic_handle_crq
function.
Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This reserved area should be eight bytes in length instead of four.
As a result, the return codes in the REQUEST_MAP_RSP descriptors
were not being properly handled.
Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Currently in both ipv4 and ipv6 code path, the ack packet received when
sk at TCP_NEW_SYN_RECV state is not filtered by socket filter or cgroup
filter since it is handled from tcp_child_process and never reaches the
tcp_filter inside tcp_v4_rcv or tcp_v6_rcv. Adding a tcp_filter hooks
here can make sure all the ingress tcp packet can be correctly filtered.
Signed-off-by: Chenbo Feng <fengc@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The memcpy annotation triggers for a fixed-length buffer copy:

In file included from /git/arm-soc/arch/arm64/include/asm/processor.h:30:0,
                 from /git/arm-soc/arch/arm64/include/asm/spinlock.h:21,
                 from /git/arm-soc/include/linux/spinlock.h:87,
                 from /git/arm-soc/include/linux/seqlock.h:35,
                 from /git/arm-soc/include/linux/time.h:5,
                 from /git/arm-soc/include/linux/stat.h:21,
                 from /git/arm-soc/include/linux/module.h:10,
                 from /git/arm-soc/drivers/net/phy/smsc.c:20:
In function 'memcpy',
    inlined from 'smsc_get_strings' at /git/arm-soc/drivers/net/phy/smsc.c:166:3:
/git/arm-soc/include/linux/string.h:309:4: error: call to '__read_overflow2' declared with attribute error: detected read beyond size of object passed as 2nd parameter

Using strncpy instead of memcpy should do the right thing here.

Fixes: 030a8902 ("net: phy: smsc: Implement PHY statistics")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

Use Mellanox device ID definitions in the driver's mlx5 ID table so tools
such as 'grep' and 'cscope' can be used to help find correlated material
(such as INTx Masking quirks: d76d2fe0 PCI: Convert Mellanox broken
INTx quirks to be for listed devices only).

No functional change intended.
Signed-off-by: Myron Stowe <myron.stowe@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Only compile-tested - I don't have the hardware.

>From code inspection, octeon_pci_write_core_mem() appears to be safe wrt
unaligned source. In any case, u8 fbuf[] was not guaranteed to be aligned
anyway.
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Felix Manlunas <felix.manlunas@cavium.com>
CC: Prasad Kanneganti <prasad.kanneganti@cavium.com>
CC: Derek Chickles <derek.chickles@cavium.com>
CC: David Miller <davem@davemloft.net>
CC: netdev@vger.kernel.org
CC: linux-kernel@vger.kernel.org
Acked-by: Felix Manlunas <felix.manlunas@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Two entries being added at the same time to the IFLA
policy table, whilst parallel bug fixes to decnet
routing dst handling overlapping with the dst gc removal
in net-next.
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull networking fixes from David Miller:

 1) Fix refcounting wrt timers which hold onto inet6 address objects,
    from Xin Long.

 2) Fix an ancient bug in wireless wext ioctls, from Johannes Berg.

 3) Firmware handling fixes in brcm80211 driver, from Arend Van Spriel.

 4) Several mlx5 driver fixes (firmware readiness, timestamp cap
    reporting, devlink command validity checking, tc offloading, etc.)
    From Eli Cohen, Maor Dickman, Chris Mi, and Or Gerlitz.

 5) Fix dst leak in IP/IP6 tunnels, from Haishuang Yan.

 6) Fix dst refcount bug in decnet, from Wei Wang.

 7) Netdev can be double freed in register_vlan_device(). Fix from Gao
    Feng.

 8) Don't allow object to be destroyed while it is being dumped in SCTP,
    from Xin Long.

 9) Fix dpaa_eth build when modular, from Madalin Bucur.

10) Fix throw route leaks, from Serhey Popovych.

11) IFLA_GROUP missing from if_nlmsg_size() and ifla_policy[] table,
    also from Serhey Popovych.

12) Fix premature TX SKB free in stmmac, from Niklas Cassel.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (36 commits)
  igmp: add a missing spin_lock_init()
  net: stmmac: free an skb first when there are no longer any descriptors using it
  sfc: remove duplicate up_write on VF filter_sem
  rtnetlink: add IFLA_GROUP to ifla_policy
  ipv6: Do not leak throw route references
  dt-bindings: net: sms911x: Add missing optional VDD regulators
  dpaa_eth: reuse the dma_ops provided by the FMan MAC device
  fsl/fman: propagate dma_ops
  net/core: remove explicit do_softirq() from busy_poll_stop()
  fib_rules: Resolve goto rules target on delete
  sctp: ensure ep is not destroyed before doing the dump
  net/hns:bugfix of ethtool -t phy self_test
  net: 8021q: Fix one possible panic caused by BUG_ON in free_netdev
  cxgb4: notify uP to route ctrlq compl to rdma rspq
  ip6_tunnel: Correct tos value in collect_md mode
  decnet: always not take dst->__refcnt when inserting dst into hash table
  ip6_tunnel: fix potential issue in __ip6_tnl_rcv
  ip_tunnel: fix potential issue in ip_tunnel_rcv
  brcmfmac: fix uninitialized warning in brcmf_usb_probe_phase2()
  net/mlx5e: Avoid doing a cleanup call if the profile doesn't have it
  ...

Michal Kalderon says:

====================
qed*: File split and rename towards iWARP support

This patch series makes a few more infrastructure changes towards adding
iWARP support. Hopefully this is the last infrastructure change
prior to the iWARP RFC.

Patch #1-3 take care of taking all the common iWARP/RoCE code out of
qed_roce.[ch] and placing it in qed_rdma.[ch]
Patch #4 renames the roce interface file as it is common for
RoCE and iWARP. This patch touches qedr as well.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Rename the qed_roce_if file to qed_rdma_if as it
represents a common interface for RoCE and iWARP.

this commit affects RDMA/qedr as well.
Signed-off-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Signed-off-by: Yuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch places common iWARP / RoCE code in qed_rdma
and roce specific code in qed_roce

There is one new function ( qed_roce_setup ) added, the rest
of the patch removes content from the files and removes some
static definitions.
Signed-off-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Signed-off-by: Yuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch adds files that will contain common code for RoCE/iWARP.
The files are currently identical to qed_roce.c / qed_roce.h and
intentionally not added to the makefile. The next patch in the series
will modify the files so that roce specific code is left in qed_roce
and common roce/iwarp code will be placed in qed_rdma

This patch is the result of a simple
cp qed_rdma.c qed_roce.c
cp qed_rdma.h qed_roce.h
Signed-off-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Signed-off-by: Yuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The next patch in the series will duplicate qed_roce as part
of code preprations for iWARP support. Do some cleanup before
duplicating
Signed-off-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Signed-off-by: Yuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull more pin control fixes from Linus Walleij:
 "Some late arriving fixes. I should have sent earlier, just swamped
  with work as usual. Thomas patch makes AMD systems usable despite
  firmware bugs so it is fairly important.

   - Make the AMD driver use a regular interrupt rather than a chained
     one, so the system does not lock up.

   - Fix a function call error deep inside the STM32 driver"

* tag 'pinctrl-v4.12-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
  pinctrl: stm32: Fix bad function call
  pinctrl/amd: Use regular interrupt instead of chained

In order to be able to retrieve the attached programs from cls_bpf
and act_bpf, we need to expose the prog ids via netlink so that
an application can later on get an fd based on the id through the
BPF_PROG_GET_FD_BY_ID command, and dump related prog info via
BPF_OBJ_GET_INFO_BY_FD command for bpf(2).
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull HID fixes from Jiri Kosina:

 - revert of a commit to magicmouse driver that regressess certain
   devices, from Daniel Stone

 - quirk for a specific Dell mouse, from Sebastian Parschauer

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid:
  Revert "HID: magicmouse: Set multi-touch keybits for Magic Mouse"
  HID: Add quirk for Dell PIXART OEM mouse

Pull livepatching fix from Jiri Kosina:
 "Fix the way how livepatches are being stacked with respect to RCU,
  from Petr Mladek"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching:
  livepatch: Fix stacking of patches with respect to RCU

Pull more ufs fixes from Al Viro:
 "More UFS fixes, unfortunately including build regression fix for the
  64-bit s_dsize commit. Fixed in this pile:

   - trivial bug in signedness of 32bit timestamps on ufs1

   - ESTALE instead of ufs_error() when doing open-by-fhandle on
     something deleted

   - build regression on 32bit in ufs_new_fragments() - calculating that
     many percents of u64 pulls libgcc stuff on some of those. Mea
     culpa.

   - fix hysteresis loop broken by typo in 2.4.14.7 (right next to the
     location of previous bug).

   - fix the insane limits of said hysteresis loop on filesystems with
     very low percentage of reserved blocks. If it's 5% or less, just
     use the OPTSPACE policy.

   - calculate those limits once and mount time.

  This tree does pass xfstests clean (both ufs1 and ufs2) and it _does_
  survive cross-builds.

  Again, my apologies for missing that, especially since I have noticed
  a related percentage-of-64bit issue in earlier patches (when dealing
  with amount of reserved blocks). Self-LART applied..."

* 'ufs-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  ufs: fix the logics for tail relocation
  ufs_iget(): fail with -ESTALE on deleted inode
  fix signedness of timestamps on ufs1

Fix expand_upwards() on architectures with an upward-growing stack (parisc,
metag and partly IA-64) to allow the stack to reliably grow exactly up to
the address space limit given by TASK_SIZE.
Signed-off-by: Helge Deller <deller@gmx.de>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Trinity gets kernel BUG at mm/mmap.c:1963! in about 3 minutes of
mmap testing.  That's the VM_BUG_ON(gap_end < gap_start) at the
end of unmapped_area_topdown().  Linus points out how MAP_FIXED
(which does not have to respect our stack guard gap intentions)
could result in gap_end below gap_start there.  Fix that, and
the similar case in its alternative, unmapped_area().

Cc: stable@vger.kernel.org
Fixes: 1be7107f ("mm: larger stack guard gap, between vmas")
Reported-by: Dave Jones <davej@codemonkey.org.uk>
Debugged-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

for connected socket, the incoming_cpu field in the sock struct
is not going to change frequently, but we are setting it
unconditionally for each packet.

Since sk_incoming_cpu and sk_flags share the same cacheline,
and the latter is access by udp_recvmsg(), this cause a cache
miss for each packet for UDP connected socket.

With this patch, we set the incoming cpu field only when the
ingress cpu really changes.

This gives a small but measurable performance improvement for
connected UDP socket.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This adds the new getsockopt(2) option SO_PEERGROUPS on SOL_SOCKET to
retrieve the auxiliary groups of the remote peer. It is designed to
naturally extend SO_PEERCRED. That is, the underlying data is from the
same credentials. Regarding its syntax, it is based on SO_PEERSEC. That
is, if the provided buffer is too small, ERANGE is returned and @optlen
is updated. Otherwise, the information is copied, @optlen is set to the
actual size, and 0 is returned.

While SO_PEERCRED (and thus `struct ucred') already returns the primary
group, it lacks the auxiliary group vector. However, nearly all access
controls (including kernel side VFS and SYSVIPC, but also user-space
polkit, DBus, ...) consider the entire set of groups, rather than just
the primary group. But this is currently not possible with pure
SO_PEERCRED. Instead, user-space has to work around this and query the
system database for the auxiliary groups of a UID retrieved via
SO_PEERCRED.

Unfortunately, there is no race-free way to query the auxiliary groups
of the PID/UID retrieved via SO_PEERCRED. Hence, the current user-space
solution is to use getgrouplist(3p), which itself falls back to NSS and
whatever is configured in nsswitch.conf(3). This effectively checks
which groups we *would* assign to the user if it logged in *now*. On
normal systems it is as easy as reading /etc/group, but with NSS it can
resort to quering network databases (eg., LDAP), using IPC or network
communication.

Long story short: Whenever we want to use auxiliary groups for access
checks on IPC, we need further IPC to talk to the user/group databases,
rather than just relying on SO_PEERCRED and the incoming socket. This
is unfortunate, and might even result in dead-locks if the database
query uses the same IPC as the original request.

So far, those recursions / dead-locks have been avoided by using
primitive IPC for all crucial NSS modules. However, we want to avoid
re-inventing the wheel for each NSS module that might be involved in
user/group queries. Hence, we would preferably make DBus (and other IPC
that supports access-management based on groups) work without resorting
to the user/group database. This new SO_PEERGROUPS ioctl would allow us
to make dbus-daemon work without ever calling into NSS.

Cc: Michal Sekletar <msekleta@redhat.com>
Cc: Simon McVittie <simon.mcvittie@collabora.co.uk>
Reviewed-by: Tom Gundersen <teg@jklm.no>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

On UDP packets processing, if the BH is the bottle-neck, it
always sees a cache miss while updating rmem_alloc; try to
avoid it prefetching the value as soon as we have the socket
available.

Performances under flood with multiple NIC rx queues used are
unaffected, but when a single NIC rx queue is in use, this
gives ~10% performance improvement.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When CONFIG_QED_RDMA isn't defined, we'd hit the following:

 /include/linux/qed/qede_rdma.h:84:19:
 warning: ‘qede_rdma_dev_add’ used but never defined [enabled by default]
 static inline int qede_rdma_dev_add(struct qede_dev *dev);

Fixes: bbfcd1e8 ("qed*: Set rdma generic functions prefix")
Signed-off-by: Chad Dupuis <chad.dupuis@cavium.com>
Signed-off-by: Yuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Replace VLAN_HLEN and CRC_SIZE with ETH_FCS_LEN.
Signed-off-by: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Jeff Kirsher says:

====================
40GbE Intel Wired LAN Driver Updates 2017-06-20

This series contains updates to i40e and i40evf only.

Björn adds additional XDP support for i40e, by adding pass and drop actions
and XDP_TX action support.

Jake fixes a possible NULL pointer dereference in
i40evf_get_ethtool_stats() which could occur if the VF fails to recover
from a reset, and then a user requests statistics.  Changed the use of
dev_info() to dev_dbg() for vf_capability client routine so that the
standard log is not spammed with this information which "might" cause
administrators to worry.  Also added more code comments to help explain
why udp_port has be in host byte order and to avoid future changes which
may cause this to break.  Fixed the holding of the RTNL lock for the
entire reset routine, reduced the scope so that the reset function will
handle its own lock, so that we do not have to wrap every reference
to i40e_do_reset() with RTNL lock/unlock.

Alice updates flags related to firmware interactions for WoL and admin
queue command address with the correct value.

Sudheer makes a fix to ensure that the array is not accessed past the
size of the array.

Greg fixes the parsing of firmware 4.33 admin queue commmand "Get CEE
DCBX PER CFG" because the firmware now creates the oper_prio_tc nibbles
reversed from those in the CDD Priority Group sub-TLV.

Carolyn adds a check and message to let users know that when in MFP mode,
changing RSS hash input set is not supported.

Shannon makes the partition bandwidth control more generic since it is not
in just one form of multi-function partitioning (MFP).  Also fixes a bug
which was causing the firmware confusion in some reset sequences, when
we were disabling interrupts and we were clearing the whole register.
Instead we should only be clearing the CAUSE_ENA bit when disabling
interrupts.

Filip adds support for OEM firmware version, so that if a OEM specific
adapter is detected, ethtool reports the OEM product version in the
firmware version string instead of etrack id.

Alan fixes a bug where the driver was not correctly exiting overflow
promiscuous mode, which can happen if "too many" MAC filters are added,
putting the driver into overflow promiscuous mode, and the filters are
then removed.  The bug occurs because the conditional for toggling
promiscuous mode was only be executed when enabled and not when it was
disabled.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Julien Gomes says:

====================
ipmr/ip6mr: add Netlink notifications on cache reports

Currently, all ipmr/ip6mr cache reports are sent through the
mroute/mroute6 socket only.
This forces the use of a single socket for mroute programming, cache
reports and, regarding ipmr, IGMP messages without Router Alert option
reception.

The present patches are aiming to send Netlink notifications in addition
to the existing igmpmsg/mrt6msg to give user programs a way to handle
cache reports in parallel with multiple sockets other than the
mroute/mroute6 socket.

Changes in v2:
- Changed attributes naming from {IPMRA,IP6MRA}_CACHEREPORTA_* to
  {IPMRA,IP6MRA}_CREPORT_*
- Improved packet data copy to handle non-linear packets in
  ipmr/ip6mr cache report Netlink notification creation
- Added two rtnetlink groups with restricted-binding
- Changed cache report notified groups from RTNL_{IPV4,IPV6}_MROUTE to
  the new restricted groups in ipmr/ip6mr

Changes in v3:
- Put message size calculation for {igmp,mrt6}msg_netlink_event in separate
  functions
- Increased vif id attributes size from u8 to u32
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Add Netlink notifications on cache reports in ip6mr, in addition to the
existing mrt6msg sent to mroute6_sk.
Send RTM_NEWCACHEREPORT notifications to RTNLGRP_IPV6_MROUTE_R.

MSGTYPE, MIF_ID, SRC_ADDR and DST_ADDR Netlink attributes contain the
same data as their equivalent fields in the mrt6msg header.
PKT attribute is the packet sent to mroute6_sk, without the added
mrt6msg header.
Suggested-by: Ryan Halbrook <halbrook@arista.com>
Signed-off-by: Julien Gomes <julien@arista.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>