Ensure that in state ESTABLISHED, where the connection is represented
by a tcp_sock, we rate limit dupacks in response to incoming packets
(a) with TCP timestamps that fail PAWS checks, or (b) with sequence
numbers or ACK numbers that are out of the acceptable window.

We do not send a dupack in response to out-of-window packets if it has
been less than sysctl_tcp_invalid_ratelimit (default 500ms) since we
last sent a dupack in response to an out-of-window packet.

There is already a similar (although global) rate-limiting mechanism
for "challenge ACKs". When deciding whether to send a challence ACK,
we first consult the new per-connection rate limit, and then the
global rate limit.
Reported-by: NAvery Fay <avery@mixpanel.com>
Signed-off-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NYuchung Cheng <ycheng@google.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the SYN_RECV state, where the TCP connection is represented by
tcp_request_sock, we now rate-limit SYNACKs in response to a client's
retransmitted SYNs: we do not send a SYNACK in response to client SYN
if it has been less than sysctl_tcp_invalid_ratelimit (default 500ms)
since we last sent a SYNACK in response to a client's retransmitted
SYN.

This allows the vast majority of legitimate client connections to
proceed unimpeded, even for the most aggressive platforms, iOS and
MacOS, which actually retransmit SYNs 1-second intervals for several
times in a row. They use SYN RTO timeouts following the progression:
1,1,1,1,1,2,4,8,16,32.
Reported-by: NAvery Fay <avery@mixpanel.com>
Signed-off-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NYuchung Cheng <ycheng@google.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some existing rhashtable users get too intimate with it by walking
the buckets directly.  This prevents us from easily changing the
internals of rhashtable.

This patch adds the helpers rhashtable_walk_init/exit/start/next/stop
which will replace these custom walkers.

They are meant to be usable for both procfs seq_file walks as well
as walking by a netlink dump.  The iterator structure should fit
inside a netlink dump cb structure, with at least one element to
spare.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Supply interface functions to bond and unbond ports of a mlx4 internal
interfaces. Example for such an interface is the one registered by the
mlx4 IB driver under RoCE.

There are

1. Functions to go in/out to/from bonded mode
2. Function to remap virtual ports to physical ports

The bond_mutex prevents simultaneous access to data that keep status of
the device in bonded mode.

The upper mlx4 interface marks to the mlx4 core module that they
want to be subject for such bonding by setting the MLX4_INTFF_BONDING
flag. Interface which goes to/from bonded mode is re-created.

The mlx4 Ethernet driver does not set this flag when registering the
interface, the IB driver does.
Signed-off-by: NMoni Shoua <monis@mellanox.com>
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Implement the hardware interface required for port aggregation.

1. Disable RX port check on receive - don't perform a validity check
that matches to QP's port and the port where the packet is received.

2. Virtual to physical port remap - configure virtual to physical port
mapping. Port remap capability for virtual functions.
Signed-off-by: NMoni Shoua <monis@mellanox.com>
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add event which provides an indication on a change in the state
of a bonding slave. The event handler should cast the pointer to the
appropriate type (struct netdev_bonding_info) in order to get the
full info about the slave.
Signed-off-by: NMoni Shoua <monis@mellanox.com>
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds skb_remcsum_process and skb_gro_remcsum_process to
perform the appropriate adjustments to the skb when receiving
remote checksum offload.

Updated vxlan and gue to use these functions.

Tested: Ran TCP_RR and TCP_STREAM netperf for VXLAN and GUE, did
not see any change in performance.
Signed-off-by: NTom Herbert <therbert@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A typical qdisc setup is the following :

bond0 : bonding device, using HTB hierarchy
eth1/eth2 : slaves, multiqueue NIC, using MQ + FQ qdisc

XPS allows to spread packets on specific tx queues, based on the cpu
doing the send.

Problem is that dequeues from bond0 qdisc can happen on random cpus,
due to the fact that qdisc_run() can dequeue a batch of packets.

CPUA -> queue packet P1 on bond0 qdisc, P1->ooo_okay=1
CPUA -> queue packet P2 on bond0 qdisc, P2->ooo_okay=0

CPUB -> dequeue packet P1 from bond0
        enqueue packet on eth1/eth2
CPUC -> dequeue packet P2 from bond0
        enqueue packet on eth1/eth2 using sk cache (ooo_okay is 0)

get_xps_queue() then might select wrong queue for P1, since current cpu
might be different than CPUA.

P2 might be sent on the old queue (stored in sk->sk_tx_queue_mapping),
if CPUC runs a bit faster (or CPUB spins a bit on qdisc lock)

Effect of this bug is TCP reorders, and more generally not optimal
TX queue placement. (A victim bulk flow can be migrated to the wrong TX
queue for a while)

To fix this, we have to record sender cpu number the first time
dev_queue_xmit() is called for one tx skb.

We can union napi_id (used on receive path) and sender_cpu,
granted we clear sender_cpu in skb_scrub_packet() (credit to Willem for
this union idea)
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Nandita Dukkipati <nanditad@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

it has just verified that it asks no more than the length of the
first segment of iovec.

And with that the last user of stuff in lib/iovec.c is gone.
RIP.

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Nicholas A. Bellinger <nab@linux-iscsi.org>
Cc: kvm@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: kvm@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: kvm@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

That takes care of the majority of ->sendmsg() instances - most of them
via memcpy_to_msg() or assorted getfrag() callbacks.  One place where we
still keep memcpy_fromiovecend() is tipc - there we potentially read the
same data over and over; separate patch, that...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Convert skb_add_data() to iov_iter; allows to get rid of the explicit
messing with iovec in its only caller - skb_add_data() will keep advancing
->msg_iter for us, so there's no need to similate that manually.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Switch from passing msg->iov_iter.iov to passing msg itself
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Commit de966c59 (net/mlx4_core: Support more than 64 VFs) was meant to
allow up to 126 VFs.  However, due to leaving MLX4_MFUNC_MAX too low, using
more than 80 VFs resulted in memory corruptions (and Oopses) when more than
80 VFs were requested. In addition, the number of slaves was left too high.

This commit fixes these issues.

Fixes: de966c59 ("net/mlx4_core: Support more than 64 VFs")
Signed-off-by: NJack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: NAmir Vadai <amirv@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pull IPv6 cork initialization into its own function that
can be re-used.  IPv6 specific cork data did not have an
explicit data structure.  This patch creats eone so that
just ipv6 cork data can be as arguemts.  Also, since
IPv6 tries to save the flow label into inet_cork_full
tructure, pass the full cork.

Adjust ip6_cork_release() to take cork data structures.
Signed-off-by: NVladislav Yasevich <vyasevic@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

bridge flags are needed inside ndo_bridge_setlink/dellink handlers to
avoid another call to parse IFLA_AF_SPEC inside these handlers

This is used later in this series
Signed-off-by: NRoopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is a high level feature flag for all switch asic offloads

switch drivers set this flag on switch ports. Logical devices like
bridge, bonds, vxlans can inherit this flag from their slaves/ports.

The patch also adds the flag to NETIF_F_ONE_FOR_ALL, so that it gets
propagated to the upperdevices (bridges and bonds).
Signed-off-by: NRoopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 8eb23b9f ("sched: Debug nested sleeps") added code to report
on nested sleep conditions, which we generally want to avoid because the
inner sleeping operation can re-set the thread state to TASK_RUNNING,
but that will then cause the outer sleep loop not actually sleep when it
calls schedule.

However, that's actually valid traditional behavior, with the inner
sleep being some fairly rare case (like taking a sleeping lock that
normally doesn't actually need to sleep).

And the debug code would actually change the state of the task to
TASK_RUNNING internally, which makes that kind of traditional and
working code not work at all, because now the nested sleep doesn't just
sometimes cause the outer one to not block, but will cause it to happen
every time.

In particular, it will cause the cardbus kernel daemon (pccardd) to
basically busy-loop doing scheduling, converting a laptop into a heater,
as reported by Bruno Prémont.  But there may be other legacy uses of
that nested sleep model in other drivers that are also likely to never
get converted to the new model.

This fixes both cases:

 - don't set TASK_RUNNING when the nested condition happens (note: even
   if WARN_ONCE() only _warns_ once, the return value isn't whether the
   warning happened, but whether the condition for the warning was true.
   So despite the warning only happening once, the "if (WARN_ON(..))"
   would trigger for every nested sleep.

 - in the cases where we knowingly disable the warning by using
   "sched_annotate_sleep()", don't change the task state (that is used
   for all core scheduling decisions), instead use '->task_state_change'
   that is used for the debugging decision itself.

(Credit for the second part of the fix goes to Oleg Nesterov: "Can't we
avoid this subtle change in behaviour DEBUG_ATOMIC_SLEEP adds?" with the
suggested change to use 'task_state_change' as part of the test)
Reported-and-bisected-by: NBruno Prémont <bonbons@linux-vserver.org>
Tested-by: NRafael J Wysocki <rjw@rjwysocki.net>
Acked-by: NOleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>,
Cc: Ilya Dryomov <ilya.dryomov@inktank.com>,
Cc: Mike Galbraith <umgwanakikbuti@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Hurley <peter@hurleysoftware.com>,
Cc: Davidlohr Bueso <dave@stgolabs.net>,
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

vlan_get_protocol() could not get network protocol if a skb has a 802.1ad
vlan tag or multiple vlans, which caused incorrect checksum calculation
in several drivers.

Fix vlan_get_protocol() to retrieve network protocol instead of incorrect
vlan protocol.

As the logic is the same as skb_network_protocol(), create a common helper
function __vlan_get_protocol() and call it from existing functions.
Signed-off-by: NToshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When many pf_packet listeners are created on a lot of interfaces the
current implementation using global packet type lists scales poorly.
This patch adds per net_device packet type lists to fix this problem.

The patch was originally written by Eric Biederman for linux-2.6.29.
Tested on linux-3.16.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NSalam Noureddine <noureddine@arista.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The core VM already knows about VM_FAULT_SIGBUS, but cannot return a
"you should SIGSEGV" error, because the SIGSEGV case was generally
handled by the caller - usually the architecture fault handler.

That results in lots of duplication - all the architecture fault
handlers end up doing very similar "look up vma, check permissions, do
retries etc" - but it generally works.  However, there are cases where
the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV.

In particular, when accessing the stack guard page, libsigsegv expects a
SIGSEGV.  And it usually got one, because the stack growth is handled by
that duplicated architecture fault handler.

However, when the generic VM layer started propagating the error return
from the stack expansion in commit fee7e49d ("mm: propagate error
from stack expansion even for guard page"), that now exposed the
existing VM_FAULT_SIGBUS result to user space.  And user space really
expected SIGSEGV, not SIGBUS.

To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those
duplicate architecture fault handlers about it.  They all already have
the code to handle SIGSEGV, so it's about just tying that new return
value to the existing code, but it's all a bit annoying.

This is the mindless minimal patch to do this.  A more extensive patch
would be to try to gather up the mostly shared fault handling logic into
one generic helper routine, and long-term we really should do that
cleanup.

Just from this patch, you can generally see that most architectures just
copied (directly or indirectly) the old x86 way of doing things, but in
the meantime that original x86 model has been improved to hold the VM
semaphore for shorter times etc and to handle VM_FAULT_RETRY and other
"newer" things, so it would be a good idea to bring all those
improvements to the generic case and teach other architectures about
them too.
Reported-and-tested-by: NTakashi Iwai <tiwai@suse.de>
Tested-by: NJan Engelhardt <jengelh@inai.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The fix from 9fc81d87 ("perf: Fix events installation during
moving group") was incomplete in that it failed to recognise that
creating a group with events for different CPUs is semantically
broken -- they cannot be co-scheduled.

Furthermore, it leads to real breakage where, when we create an event
for CPU Y and then migrate it to form a group on CPU X, the code gets
confused where the counter is programmed -- triggered in practice
as well by me via the perf fuzzer.

Fix this by tightening the rules for creating groups. Only allow
grouping of counters that can be co-scheduled in the same context.
This means for the same task and/or the same cpu.

Fixes: 9fc81d87 ("perf: Fix events installation during moving group")
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20150123125834.090683288@infradead.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

Currently ->get_dqblk() and ->set_dqblk() use struct fs_disk_quota which
tracks space limits and usage in 512-byte blocks. However VFS quotas
track usage in bytes (as some filesystems require that) and we need to
somehow pass this information. Upto now it wasn't a problem because we
didn't do any unit conversion (thus VFS quota routines happily stuck
number of bytes into d_bcount field of struct fd_disk_quota). Only if
you tried to use Q_XGETQUOTA or Q_XSETQLIM for VFS quotas (or Q_GETQUOTA
/ Q_SETQUOTA for XFS quotas), you got bogus results. Hardly anyone
tried this but reportedly some Samba users hit the problem in practice.
So when we want interfaces compatible we need to fix this.

We bite the bullet and define another quota structure used for passing
information from/to ->get_dqblk()/->set_dqblk. It's somewhat sad we have
to have more conversion routines in fs/quota/quota.c and another copying
of quota structure slows down getting of quota information by about 2%
but it seems cleaner than overloading e.g. units of d_bcount to bytes.

CC: stable@vger.kernel.org
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJan Kara <jack@suse.cz>

The firmware spec states that the timeout for all commands should be 60 seconds.

In the past, the spec indicated that there were several classes of timeout
(short, medium, and long).  The driver has these different timeout classes.
We leave the class differentiation in the driver as-is (to protect against any
future spec changes), but set the timeout for all classes to be 60 seconds.

In addition, we fix a few commands which had hard-coded numeric timeouts specified.
Signed-off-by: NJack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: NAmir Vadai <amirv@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If the firmware can detect a bad cable, allow it to generate an
event, and print the problem in the log.
Signed-off-by: NJack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: NAmir Vadai <amirv@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

st21nfca has 1 physical SWP line and can support up to 2 secure elements
(UICC & eSE) thanks to an external switch managed with a gpio.

The platform integrator needs to specify thanks to 2 initialization
properties, uicc-present and ese-present, if it is suppose to have uicc
and/or ese. Of course if the platform does not have an external switch,
only one kind of secure element can be supported. Those parameters are
under platform integrator responsibilities.

During initialization, the white_list will be set according to those
parameters.

The discovery_se function will assume a secure element is physically
present according to uicc-present and ese-present values and will add it
to the secure element list. On ese activation, the atr is retrieved to
calculate a command exchange timeout based on the first atr(TB) value.

The se_io will allow to transfer data over SWP. 2 kind of events may appear
after a data is sent over:
- ST21NFCA_EVT_TRANSMIT_DATA when receiving an apdu answer
- ST21NFCA_EVT_WTX_REQUEST when the secure element needs more time than
expected to compute a command. If this timeout expired, a first recovery
tentative consist to send a simple software reset proprietary command.
If this tentative still fail, a second recovery tentative consist to send
a hardware reset proprietary command.
This function is only relevant for eSE like secure element.

This patch also change the way a pipe is referenced. There can be
different pipe connected to the same gate with different host destination
(ex: CONNECTIVITY). In order to keep host information every pipe are
reference with a tuple (gate, host). In order to reduce changes, we are
keeping unchanged the way a gate is addressed on the Terminal Host.
However, this is working because we consider the apdu reader gate is only
present on the eSE slot also the connectivity gate cannot give a reliable
value; it will give the latest stored pipe value.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

This allows mac80211 to configure BIP-CMAC-256 to the driver and also
use software-implementation within mac80211 when the driver does not
support this with hardware accelaration.
Signed-off-by: NJouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

This makes cfg80211 aware of the GCMP, GCMP-256, CCMP-256, BIP-GMAC-128,
BIP-GMAC-256, and BIP-CMAC-256 cipher suites. These new cipher suites
were defined in IEEE Std 802.11ac-2013.
Signed-off-by: NJouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

In order to avoid double calls to phydev->drv->suspend and resume, keep
track of whether the PHY has already been suspended as a consequence of
a successful call to phy_suspend(). We will use this in our MDIO bus
suspend/resume hooks to avoid a double suspend call.
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

has_fixups was introduced to help keeping track of fixups/quirks running
on a PHY device, but we did not update the comment above struct
phy_device accordingly.

Fixes: b0ae009f (net: phy: add "has_fixups" boolean property")
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/linux/platform_data/st21nfcb.h is based on
include/linux/platform_data/st21nfca.h.

The endif comment is inacurrate for st21nfcb.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

include/linux/platform_data/st21nfcb.h is phy generic.
There is no need to include linux/i2c.h
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

There are missing dummy routines for log_buf_addr_get() and
log_buf_len_get() for when CONFIG_PRINTK is not set causing build
failures.

This patch adds these dummy routines at the appropriate location.
Signed-off-by: NPranith Kumar <bobby.prani@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: NPetr Mladek <pmladek@suse.cz>
Acked-by: NSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The OOM killing invocation does a lot of duplicative checks against the
task's allocation context.  Rework it to take advantage of the existing
checks in the allocator slowpath.

The OOM killer is invoked when the allocator is unable to reclaim any
pages but the allocation has to keep looping.  Instead of having a check
for __GFP_NORETRY hidden in oom_gfp_allowed(), just move the OOM
invocation to the true branch of should_alloc_retry().  The __GFP_FS
check from oom_gfp_allowed() can then be moved into the OOM avoidance
branch in __alloc_pages_may_oom(), along with the PF_DUMPCORE test.

__alloc_pages_may_oom() can then signal to the caller whether the OOM
killer was invoked, instead of requiring it to duplicate the order and
high_zoneidx checks to guess this when deciding whether to continue.
Signed-off-by: NJohannes Weiner <hannes@cmpxchg.org>
Acked-by: NMichal Hocko <mhocko@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Make the slave support depend on CONFIG_I2C_SLAVE. Otherwise it gets
included unconditionally, even when it is not needed.

I2C bus drivers which implement slave support must select
I2C_SLAVE.
Signed-off-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

"next" is not updated, causing an endless loop for buckets with more than
one element.

Fixes: 88d6ed15 ("rhashtable: Convert bucket iterators to take table and index")
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Acked-by: NThomas Graf <tgraf@suug.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The kernel forcefully applies MTU values received in router
advertisements provided the new MTU is less than the current. This
behavior is undesirable when the user space is managing the MTU. Instead
a sysctl flag 'accept_ra_mtu' is introduced such that the user space
can control whether or not RA provided MTU updates should be applied. The
default behavior is unchanged; user space must explicitly set this flag
to 0 for RA MTUs to be ignored.
Signed-off-by: NHarout Hedeshian <harouth@codeaurora.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In SRIOV, both the PF and the VF may attempt device recovery whenever they
assume that the device is not functioning.  When the PF driver resets the
device, the VF should detect this and attempt to reinitialize itself.

The VF must be able to reset itself under all circumstances, even
if the PF is not responsive.

The VF shall reset itself in the following cases:

1. Commands are not processed within reasonable time over the communication channel.
This is done considering device state and the correct return code based on
the command as was done in the native mode, done in the next patch.

2. The VF driver receives an internal error event reported by the PF on the
communication channel. This occurs when the PF driver resets the device or
when VF is out of sync with the PF.

Add 'VF reset' capability, which allows the VF to reinitialize itself even when the
PF is not responsive.

As PF and VF may run their reset flow simulantanisly, there are several cases
that are handled:
- Prevent freeing VF resources upon FLR, when PF is in its unloading stage.
- Prevent PF getting VF commands before it has finished initializing its resources.
- Upon VF startup, check that comm-channel is online before sending
  commands to the PF and getting timed-out.
Signed-off-by: NYishai Hadas <yishaih@mellanox.com>
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>