Followup of commit 0c24604b (tcp: implement RFC 5961 4.2)

As reported by Vijay Subramanian, we should send a challenge ACK
instead of a dup ack if a SYN flag is set on a packet received out of
window.

This permits the ratelimiting to work as intended, and to increase
correct SNMP counters.
Suggested-by: Vijay Subramanian <subramanian.vijay@gmail.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Vijay Subramanian <subramanian.vijay@gmail.com>
Cc: Kiran Kumar Kella <kkiran@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Some workloads greatly benefit of IFF_XMIT_DST_RELEASE capability
on output net device, avoiding dirtying dst refcount.

bonding currently disables IFF_XMIT_DST_RELEASE unconditionally.

If all slaves have the IFF_XMIT_DST_RELEASE bit set, then
bonding master can also have it in its priv_flags
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jay Vosburgh <fubar@us.ibm.com>
Cc: Andy Gospodarek <andy@greyhouse.net>
Cc: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The usbnet API use the device ID table to store a pointer to
a minidriver. Setting a generic pointer for dynamic device
IDs will in most cases make them work as expected.  usbnet
will otherwise treat the dynamic IDs as blacklisted. That is
rarely useful.

There is no standard class describing devices supported by
this driver, and most vendors don't even provide enough
information to allow vendor specific wildcard matching. The
result is that most of the supported devices must be
explicitly listed in the device table.  Allowing dynamic IDs
to work both simplifies testing and verification of new
devices, and provides a way for end users to use a device
before the ID is added to the driver.
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add support for 64 bit stats to Broadcom b44 ethernet driver.
Signed-off-by: Kevin Groeneveld <kgroeneveld@gmail.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The ability of driver to transmit packets depends on logical state
of the link. Ignore physical link status.
Signed-off-by: Padmanabh Ratnakar <padmanabh.ratnakar@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Lancer FW has added new capability checks for VFs.
Driver should only use those capabilities which are allowed for VFs.
Signed-off-by: Padmanabh Ratnakar <padmanabh.ratnakar@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Jerr Kirsher says:

====================
This series contains updates to ixgbe & ixgbevf.
 ...
Alexander Duyck (6):
  ixgbe: Ping the VFs on link status change to trigger link change
  ixgbe: Handle failures in the ixgbe_setup_rx/tx_resources calls
  ixgbe: Move configuration of set_real_num_rx/tx_queues into open
  ixgbe: Update the logic for ixgbe_cache_ring_dcb and DCB RSS
    configuration
  ixgbe: Cleanup logic for MRQC and MTQC configuration
  ixgbevf: Update descriptor macros to accept pointers and drop _ADV
    suffix
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Francois Romieu says:

====================
Francois Romieu (1):
      r8169: verbose error message.

Hayes Wang (1):
      r8169: remove rtl_ocpdr_cond.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Ben Hutchings says:

====================
1. Fix potential badness when running a self-test with SR-IOV enabled.
2. Fix calculation of some interface statistics that could run backward.
3. Miscellaneous cleanup.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

We should provide to inet6_csk_route_socket a struct flowi6 pointer,
so that net6_csk_xmit() works correctly instead of sending garbage.

Also add some consts
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This change updates the descriptor macros to accept pointers, updates the
name to drop the _ADV suffix, and include the IXGBEVF name in the macro.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Greg Rose <gregory.v.rose@intel.com>
Tested-by: Sibai Li <sibai.li@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

This change is meant to make the code much more readable for MTQC and MRQC
configuration.

The big change is that I simplified much of the logic so that we are
essentially handling just 4 cases and their variants. In the cases where
RSS is disabled we are actually just programming the RETA table with all
1s resulting in a single queue RSS. In the case of SR-IOV I am treating
that as a subset of VMDq. This all results int he following configuration
for the hardware:
         DCB
         En       Dis
VMDq En  VMDQ/DCB VMDq/RSS
     Dis DCB/RSS  RSS

Cc: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Stephen Ko <stephen.s.ko@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

This change cleans up some of the logic in an attempt to try and simplify
things for how we are configuring DCB w/ RSS.

In this patch I basically did 3 things.  I updated the logic for getting
the first register index.  I applied the fact that all TCs get the same
number of queues to simplify the looping logic in caching the DCB ring
register.  Finally I updated how we configure the RQTC register to match
the fact that all TCs are assigned the same number of queues.

Cc: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

It makes much more sense for us to configure the real number of Tx and Rx
queues in the ixgbe_open call than it does in ixgbe_set_num_queues.  By
setting the number in ixgbe_open we can avoid a number of unecessary
updates and only have to make the calls once.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

Previously we were exiting without cleaning up the memory internally on the
ixgbe_setup_rx_resources and ixgbe_setup_tx_resources calls.  Instead of
forcing the caller to clean things up for us we should instead just unwind
the rings and free the memory as we go.  This way we can more gracefully
clean up the rings in the event of an allocation failure.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

When the link status changes on the PF we need to notify the VFs. In order
to do this we should ping all of the VFs in order to trigger a link status
change on them as well.

This fixes issues in which the PF would reset, but the VF didn't because the
NAK flag was not set in the VF mailbox.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Tested-by: Sibai Li <sibai.li@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Cc: Hayes Wang <hayeswang@realtek.com>

It is not needed for mac_ocp_{write / read}. Actually bit 31 of OCPDR
does not change and r8168_mac_ocp_read always returns ~0.
Signed-off-by: Hayes Wang <hayeswang@realtek.com>
Tested-by: Francois Romieu <romieu@fr.zoreil.com>

free_nh_exceptions() should use rcu_dereference_protected(..., 1)
since its called after one RCU grace period.

Also add some const-ification in recent code.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Need to mask it with (FNHE_HASH_SIZE - 1).
Signed-off-by: David S. Miller <davem@davemloft.net>

These patches implement the final mechanism necessary to really allow
us to go without the route cache in ipv4.

We need a place to have long-term storage of PMTU/redirect information
which is independent of the routes themselves, yet does not get us
back into a situation where we have to write to metrics or anything
like that.

For this we use an "next-hop exception" table in the FIB nexthops.

The one thing I desperately want to avoid is having to create clone
routes in the FIB trie for this purpose, because that is very
expensive.   However, I'm willing to entertain such an idea later
if this current scheme proves to have downsides that the FIB trie
variant would not have.

In order to accomodate this any such scheme, we need to be able to
produce a full flow key at PMTU/redirect time.  That required an
adjustment of the interface call-sites used to propagate these events.

For a PMTU/redirect with a fully specified socket, we pass that socket
and use it to produce the flow key.

Otherwise we use a passed in SKB to formulate the key.  There are two
cases that need to be distinguished, ICMP message processing (in which
case the IP header is at skb->data) and output packet processing
(mostly tunnels, and in all such cases the IP header is at ip_hdr(skb)).

We also have to make the code able to handle the case where the dst
itself passed into the dst_ops->{update_pmtu,redirect} method is
invalidated.  This matters for calls from sockets that have cached
that route.  We provide a inet{,6} helper function for this purpose,
and edit SCTP specially since it caches routes at the transport rather
than socket level.
Signed-off-by: David S. Miller <davem@davemloft.net>

It's done in very similar way this is done in bonding and bridge.
Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>

In a regime where we have subnetted route entries, we need a way to
store persistent storage about destination specific learned values
such as redirects and PMTU values.

This is implemented here via nexthop exceptions.

The initial implementation is a 2048 entry hash table with relaiming
starting at chain length 5.  A more sophisticated scheme can be
devised if that proves necessary.
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>

Some interface statistics are computed in such a way that they can
sometimes decrease (and even underflow).  Since the computed value
will never be greater than the true value, we fix this by only storing
the computed value when it increases.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>

Currently VF queues and drivers may remain active during this test.
This could cause memory corruption or spurious test failures.
Therefore we reset the port/function before running these tests on
Siena.

On Falcon this doesn't work: we have to do some additional
initialisation before some blocks will work again.  So refactor the
reset/register-test sequence into an efx_nic_type method so
efx_selftest() doesn't have to consider such quirks.

In the process, fix another minor bug: Siena does not have an
'invisible' reset and the self-test currently fails to push the PHY
configuration after resetting.  Passing RESET_TYPE_ALL to
efx_reset_{down,up}() fixes this.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>

Fix CID 113952 in Coverity report on Linux.

This is the one instance where we don't, and shouldn't, check the
return code from efx_mcdi_rpc().  It wasn't immediately obvious to me
why we didn't, so I think an explanation is in order.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>

Fix CID 102619 in the Coverity report on Linux.

efx_end_loopback() iterates over an array of skb pointers of which
some may be null (if efx_begin_loopback() failed).  It should not use
dev_kfree_skb_irq(), which requires non-null pointers.  In practice
this is safe because it does not run in interrupt context and
therefore always ends up calling dev_kfree_skb(), which does allow
null pointers.  But we should make that explicit.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>

Fix CID 113703 in the Coverity report on Linux.

ethtool stats names are limited to 32 bytes including a null
terminator.  Use strlcpy() to ensure that we will always include the
null terminator even if a source string becomes longer than this.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>

There is nothing in the VLAN driver or core VLAN support that
invalidates the TCP and IP header offsets.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>

tso_state::packet_space is always set in tso_start_packet(); the
value set in tso_start() is not used, and is also incorrect.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>

With some gcc versions & optimisations, the compiler will warn that
'depth' in efx_filter_insert_filter() may be used without being
initialised, although this is not the case.

This is related to inlining of efx_filter_search(), which only has
one caller since commit 8db182f4
('sfc: Remove now-unused filter function').

Shut the compiler up by initialising it to 0.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>

Implement the RFC 5691 mitigation against Blind
Reset attack using SYN bit.

Section 4.2 of RFC 5961 advises to send a Challenge ACK and drop
incoming packet, instead of resetting the session.

Add a new SNMP counter to count number of challenge acks sent
in response to SYN packets.
(netstat -s | grep TCPSYNChallenge)

Remove obsolete TCPAbortOnSyn, since we no longer abort a TCP session
because of a SYN flag.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Kiran Kumar Kella <kkiran@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This will be used so that we can compose a full flow key.

Even though we have a route in this context, we need more.  In the
future the routes will be without destination address, source address,
etc. keying.  One ipv4 route will cover entire subnets, etc.

In this environment we have to have a way to possess persistent storage
for redirects and PMTU information.  This persistent storage will exist
in the FIB tables, and that's why we'll need to be able to rebuild a
full lookup flow key here.  Using that flow key will do a fib_lookup()
and create/update the persistent entry.
Signed-off-by: David S. Miller <davem@davemloft.net>

The interrupt registers accessed in ixgbevf are more similar to the igb
style registers than they are to the ixgbe style registers.  As such we
would be better off setting up the code for the EICS, EIMS, EICS, EIAM, and
EIAC like we do in igb instead of ixgbe.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Greg Rose <gregory.v.rose@intel.com>
Tested-by: Sibai Li <sibai.li@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

Currently the VF driver is processing all of the transmits in interrupt
context.  This can be messy since the Rx is all handled in NAPI and this
may result in interrupts being disabled.  In order to resolve this move all
of the Tx packet processing into NAPI and combine all of the interrupt and
polling routines into just a pair of functions.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Greg Rose <gregory.v.rose@intel.com>
Tested-by: Sibai Li <sibai.li@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

For most cases the ixgbevf driver will only ever contain a single Tx and
single Rx queue.  In order to track that it makes more sense to use a
pointer instead of using a bitmap which must be search in order to locate
the ring on an adapter index.  As such I am changing the code to use
pointers and an iterator to access all rings on a given q_vector.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Greg Rose <gregory.v.rose@intel.com>
Tested-by: Sibai Li <sibai.li@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

This change cleans up the accounting needed at the start of xmit_frame so
that we can avoid doing too much work to determine how many descriptors we
will need.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Greg Rose <gregory.v.rose@intel.com>
Tested-by: Sibai Li <sibai.li@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>