net/mlx4_core: Don't fail reg/unreg vlan for older guests

In upstream kernels under SRIOV, the vlan register/unregister calls
were NOPs (doing nothing and returning OK). We detect these old
calls from guests (via the comm channel), since previously the
port number in mlx4_register_vlan was passed (improperly) in the
out_param. This has been corrected so that the port number is now
passed in bits 8..15 of the in_modifier field.

For old calls, these bits will be zero, so if the passed port
number is zero, we can still look at the out_param field to see
if it contains a valid port number. If yes, the VM is running
an old driver.

Since for old drivers, the register/unregister_vlan wrappers were
NOPs, we continue this policy -- the reason being that upstream
had an additional bug in eth driver running on guests (where
procedure mlx4_en_vlan_rx_kill_vid() had the following code:

if (!mlx4_find_cached_vlan(mdev->dev, priv->port, vid, &idx))
        mlx4_unregister_vlan(mdev->dev, priv->port, idx);
else
        en_err(priv, "could not find vid %d in cache\n", vid);

On a VM, mlx4_find_cached_vlan() will always fail, since the
vlan cache is located on the Hypervisor; on guests it is empty.

Therefore, if we allow upstream guests to register vlans, we will
have vlan leakage since the unregister will never be performed.
Leaving vlan reg/unreg for old guest drivers as a NOP is not a
feature regression, since in upstream the register/unregister
vlan wrapper is a NOP.

Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/mlx4_core: Fix checking order in MR table init

In procedure mlx4_init_mr_table(), slaves should do no processing,
but should return success. This initialization is hypervisor-only.

However, the check for num_mpts being a power-of-2 was performed
before the check to return immediately if the driver is for a slave.
This resulted in spurious failures.

The order of performing the checks is reversed, so that if the
driver is for a slave, no processing is done and success is returned.

Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
mlx4: Structures and init/teardown for VF resource quotas

This is step #1 for implementing SRIOV resource quotas for VFs.

Quotas are implemented per resource type for VFs and the PF, to prevent
any entity from simply grabbing all the resources for itself and leaving
the other entities unable to obtain such resources.

Resources which are allocated using quotas:  QPs, CQs, SRQs, MPTs, MTTs, MAC,
                                             VLAN, and Counters.

The quota system works as follows:
Each entity (VF or PF) is given a max number of a given resource (its quota),
and a guaranteed minimum number for each resource (starvation prevention).

For QPs, CQs, SRQs, MPTs and MTTs:
50% of the available quantity for the resource is divided equally among
the PF and all the active VFs (i.e., the number of VFs in the mlx4_core module
parameter "num_vfs"). This 50% represents the "guaranteed minimum" pool.
The other 50% is the "free pool", allocated on a first-come-first-serve basis.
For each VF/PF, resources are first allocated from its "guaranteed-minimum"
pool. When that pool is exhausted, the driver attempts to allocate from
the resource "free-pool".

The quota (i.e., max) for the VFs and the PF is:
  The free-pool amount (50% of the real max) + the guaranteed minimum

For MACs:
  Guarantee 2 MACs per VF/PF per port. As a result, since we have only
  128 MACs per port, reduce the allowable number of VFs from 64 to 63.
  Any remaining MACs are put into a free pool.

For VLANs:
  For the PF, the per-port quota is 128 and guarantee is 64
     (to allow the PF to register at least a VLAN per VF in VST mode).
  For the VFs, the per-port quota is 64 and the guarantee is 0.
      We assume that VGT VFs are trusted not to abuse the VLAN resource.

For Counters:
  For all functions (PF and VFs), the quota is 128 and the guarantee is 0.

In this patch, we define the needed structures, which are added to the
resource-tracker struct.  In addition, we do initialization
for the resource quota, and adjust the query_device response to use quotas
rather than resource maxima.

As part of the implementation, we introduce a new field in
mlx4_dev: quotas.  This field holds the resource quotas used
to report maxima to the upper layers (ib_core, via query_device).

The HCA maxima of these values are passed to the VFs (via
QUERY_HCA) so that they may continue to use these in handling
QPs, CQs, SRQs and MPTs.

Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/mlx4_core: Fix quota handling in the QUERY_FUNC_CAP wrapper

In current kernels, the mlx4 driver running on a VM does not
differentiate between max resource numbers for the HCA and
max quotas -- it simply takes the quota values passed to it
as max-resource values.

However, the driver actually requires the VFs to be aware of
the actual number of resources that the HCA was initialized with,
for QPs, CQs, SRQs and MPTs.

For QPs, CQs and SRQs, the reason is that in completion handling
the driver must know which of the 24 bits are the actual resource
number, and which are "padding" bits.

For MPTs, also, the driver assumes knowledge of the number of MPTs
in the system.

The previous commit fixes the quota logic on the VM for the quota values
passed to it by QUERY_FUNC_CAPS.

For QPs, CQs, SRQs, and MPTs, it takes the max resource numbers
from QUERY_HCA (and not QUERY_FUNC_CAPS).  The quotas passed
in QUERY_FUNC_CAPS are used to report max resource number values
in the response to ib_query_device.

However, the Hypervisor driver must consider that VMs
may be running previous kernels, and compatibility must be preserved.

To resolve the incompatibility with previous kernels running on VMs,
we deprecated the quota fields in mlx4_QUERY_FUNC_CAP.  In the
deprecated fields, we pass the max-resource values from INIT_HCA

The quota fields are moved to a new location, and the current kernel
driver takes the proper values from that location. There is
also a new flag in dword 0, bit 28 of the mlx4_QUERY_FUNC_CAP mailbox;
if this flag is set, the (VM) driver takes the quota values from the
new location.

VMs running previous kernels will work properly, except that the max resource
numbers reported in ib_query_device for these resources will be
too high.  The Hypervisor driver will, however, enforce the quotas
for these VMs.

Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/mlx4_core: Implement resource quota enforcement

Implements resource quota grant decision when resources are requested,
for the following resources:  QPs, CQs, SRQs, MPTs, MTTs, vlans, MACs,
and Counters.

When granting a resource, the quota system increases the allocated-count
for that slave.

When the slave later frees the resource, its allocated-count is reduced.

A spinlock is used to protect the integrity of each resource's free-pool counter.
(One slave may be in the process of being granted a resource while another
slave has crashed, initiating cleanup of that slave's resource quotas).

Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Merge branch 'mlx4'

Or Gerlitz says:

====================
Mellanox driver updates

This patch set from Jack Morgenstein does the following:

1. Fix MAC/VLAN SRIOV implementation, and add wrapper functions for VLAN allocation
   and de-allocation (patches 1-6).

2. Implements resource quotas when running under SRIOV (patches 7-10).
   Patch 7 is a small bug fix, and patches 8-10 implement the quotas.

Quotas are implemented per resource type for VFs and the PF, to prevent
any entity from simply grabbing all the resources for itself and leaving
the other entities unable to obtain such resources.

The series is against net-next commit ba48650 "ipv6: remove the unnecessary statement in find_match()"

changes from V0:
 - dropped the 1st patch which needs to go to -stable and hence through net,
   not net-next
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/jesse/openvswitch

Jesse Gross says:

====================
Open vSwitch

A set of updates for net-next/3.13. Major changes are:
 * Restructure flow handling code to be more logically organized and
   easier to read.
 * Rehashing of the flow table is moved from a workqueue to flow
   installation time. Before, heavy load could block the workqueue for
   excessive periods of time.
 * Additional debugging information is provided to help diagnose megaflows.
 * It's now possible to match on TCP flags.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
netfilter: nft_compat: use _safe version of list_for_each

We need to use the _safe version of list_for_each_entry() here otherwise
we have a use after free bug.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
powerpc/boot: Properly handle the base "of" boot wrapper

The wrapper script needs an explicit rule for the "of" boot
wrapper (generic wrapper, similar to pseries). Before
0c9fa29149d3726e14262aeb0c8461a948cc9d56 it was hanlded
implicitly by the statement:

platformo=$object/"$platform".o

But now that epapr.o needs to be added, that doesn't work
and an explicit rule must be added.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
powerpc/pci: Use pci_is_pcie() to simplify code [fix]

Fix f0308261b1 ("powerpc/pci: Use pci_is_pcie() to simplify code").  I
accidentally merged v2 instead of v3, so this adds the difference.  Without
this, "cap" is the left-over PCI-X capability offset, and we're using it as
the PCIe capability offset.

[bhelgaas: extracted v2->v3 diff]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
perf hists: Consolidate __hists__add_*entry()

The __hists__add_{branch,mem}_entry() does almost the same thing that
__hists__add_entry() does.  Consolidate them into one.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Rodrigo Campos <rodrigo@sdfg.com.ar>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1383202576-28141-2-git-send-email-namhyung@kernel.org
[ Fixup clash with new COMM infrastructure ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Merge branch 'pci/yijing-pci_is_pcie-v2' into next

* pci/yijing-pci_is_pcie-v2:
  powerpc/pci: Use pci_is_pcie() to simplify code [fix]
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next

Pablo Neira Ayuso says:

====================
This is another batch containing Netfilter/IPVS updates for your net-next
tree, they are:

* Six patches to make the ipt_CLUSTERIP target support netnamespace,
  from Gao feng.

* Two cleanups for the nf_conntrack_acct infrastructure, introducing
  a new structure to encapsulate conntrack counters, from Holger
  Eitzenberger.

* Fix missing verdict in SCTP support for IPVS, from Daniel Borkmann.

* Skip checksum recalculation in SCTP support for IPVS, also from
  Daniel Borkmann.

* Fix behavioural change in xt_socket after IP early demux, from
  Florian Westphal.

* Fix bogus large memory allocation in the bitmap port set type in ipset,
  from Jozsef Kadlecsik.

* Fix possible compilation issues in the hash netnet set type in ipset,
  also from Jozsef Kadlecsik.

* Define constants to identify netlink callback data in ipset dumps,
  again from Jozsef Kadlecsik.

* Use sock_gen_put() in xt_socket to replace xt_socket_put_sk,
  from Eric Dumazet.

* Improvements for the SH scheduler in IPVS, from Alexander Frolkin.

* Remove extra delay due to unneeded rcu barrier in IPVS net namespace
  cleanup path, from Julian Anastasov.

* Save some cycles in ip6t_REJECT by skipping checksum validation in
  packets leaving from our stack, from Stanislav Fomichev.

* Fix IPVS_CMD_ATTR_MAX definition in IPVS, larger that required, from
  Julian Anastasov.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nftables

Pablo Neira Ayuso says:

====================
This batch contains fives nf_tables patches for your net-next tree,
they are:

* Fix possible use after free in the module removal path of the
  x_tables compatibility layer, from Dan Carpenter.

* Add filter chain type for the bridge family, from myself.

* Fix Kconfig dependencies of the nf_tables bridge family with
  the core, from myself.

* Fix sparse warnings in nft_nat, from Tomasz Bursztyka.

* Remove duplicated include in the IPv4 family support for nf_tables,
  from Wei Yongjun.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
tcp: enable sockets to use MSG_FASTOPEN by default

Applications have started to use Fast Open (e.g., Chrome browser has
such an optional flag) and the feature has gone through several
generations of kernels since 3.7 with many real network tests. It's
time to enable this flag by default for applications to test more
conveniently and extensively.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tcp: properly handle stretch acks in slow start

Slow start now increases cwnd by 1 if an ACK acknowledges some packets,
regardless the number of packets. Consequently slow start performance
is highly dependent on the degree of the stretch ACKs caused by
receiver or network ACK compression mechanisms (e.g., delayed-ACK,
GRO, etc).  But slow start algorithm is to send twice the amount of
packets of packets left so it should process a stretch ACK of degree
N as if N ACKs of degree 1, then exits when cwnd exceeds ssthresh. A
follow up patch will use the remainder of the N (if greater than 1)
to adjust cwnd in the congestion avoidance phase.

In addition this patch retires the experimental limited slow start
(LSS) feature. LSS has multiple drawbacks but questionable benefit. The
fractional cwnd increase in LSS requires a loop in slow start even
though it's rarely used. Configuring such an increase step via a global
sysctl on different BDPS seems hard. Finally and most importantly the
slow start overshoot concern is now better covered by the Hybrid slow
start (hystart) enabled by default.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Merge branch 'for-davem' of git://gitorious.org/linux-can/linux-can-next

Marc Kleine-Budde says:

====================
here's a pull request for net-next.

It includes a patch by Oliver Hartkopp et al. that adds documentation
for the broadcast manager to Documentation/networking/can.txt. Three
patches by me that clean up the netlink handling code in the CAN core.
And another patch that removes a not needed function from the ti_hecc
driver.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
net: codel: Avoid undefined behavior from signed overflow

As described in commit 5a581b367 (jiffies: Avoid undefined
behavior from signed overflow), according to the C standard
3.4.3p3, overflow of a signed integer results in undefined
behavior.

To fix this, do as the above commit, and do an unsigned
subtraction, and interpreting the result as a signed
two's-complement number.  This is based on the theory from
RFC 1982 and is nicely described in wikipedia here:
 https://en.wikipedia.org/wiki/Serial_number_arithmetic#General_Solution

A side-note, I have seen practical issues with the previous logic
when dealing with 16-bit, on a 64-bit machine (gcc version
4.4.5). This were 32-bit, which I have not observed issues with.

Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Jesper Dangaard Brouer <netoptimizer@brouer.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
vxlan: Use ERR_CAST inlined function instead of ERR_PTR(PTR_ERR(...))

trivial patch converting ERR_PTR(PTR_ERR()) into ERR_CAST().
No functional changes.

Signed-off-by: Duan Jiong <duanj.fnst@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: introduce skb_coalesce_rx_frag()

Sometimes we need to coalesce the rx frags to avoid frag list. One example is
virtio-net driver which tries to use small frags for both MTU sized packet and
GSO packet. So this patch introduce skb_coalesce_rx_frag() to do this.

Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Michael Dalton <mwdalton@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>