In the recent support for layer 2 hardware acceleration, I added a
few references to real_num_rx_queues and num_rx_queues which are
only available with CONFIG_RPS.

The fix is first to remove unnecessary references to num_rx_queues.
Because the hardware offload case is limited to cases where RX queues
and TX queues are equal we only need a single check. Then wrap the
single case in an ifdef.

The patch that introduce this is here,

commit a6cc0cfa
Author: John Fastabend <john.r.fastabend@intel.com>
Date:   Wed Nov 6 09:54:46 2013 -0800

    net: Add layer 2 hardware acceleration operations for macvlan devices
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NJohn Fastabend <john.r.fastabend@intel.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Acked-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As the rfc 4191 said, the Router Preference and Lifetime values in a
::/0 Route Information Option should override the preference and lifetime
values in the Router Advertisement header. But when the kernel deals with
a ::/0 Route Information Option, the rt6_get_route_info() always return
NULL, that means that overriding will not happen, because those default
routers were added without flag RTF_ROUTEINFO in rt6_add_dflt_router().

In order to deal with that condition, we should call rt6_get_dflt_router
when the prefix length is 0.
Signed-off-by: NDuan Jiong <duanj.fnst@cn.fujitsu.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 0628b123 ("netfilter: nfnetlink: add batch support and use it
from nf_tables") introduced a bug leading to various crashes in netlink_ack
when netlink message with invalid nlmsg_len was sent by an unprivileged
user.
Signed-off-by: NJiri Benc <jbenc@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When trying to delete a table >= 256 using iproute2 the local table
will be deleted.
The table id is specified as a netlink attribute when it needs more then
8 bits and iproute2 then sets the table field to RT_TABLE_UNSPEC (0).
Preconditions to matching the table id in the rule delete code
doesn't seem to take the "table id in netlink attribute" into condition
so the frh_get_table helper function never gets to do its job when
matching against current rule.
Use the helper function twice instead of peaking at the table value directly.

Originally reported at: http://bugs.debian.org/724783Reported-by: NNicolas HICHER <nhicher@avencall.com>
Signed-off-by: NAndreas Henriksson <andreas@fatal.se>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Take ip6_fl_lock before to read and update
a label.

v2: protect only the relevant code
Reported-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NFlorent Fourcot <florent.fourcot@enst-bretagne.fr>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If the last RFC 6437 does not give any constraints
for lifetime of flow labels, the previous RFC 3697
spoke of a minimum of 120 seconds between
reattribution of a flow label.

The maximum linger is currently set to 60 seconds
and does not allow this configuration without
CAP_NET_ADMIN right.

This patch increase the maximum linger to 150
seconds, allowing more flexibility to standard
users.
Signed-off-by: NFlorent Fourcot <florent.fourcot@enst-bretagne.fr>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It is already possible to set/put/renew a label
with IPV6_FLOWLABEL_MGR and setsockopt. This patch
add the possibility to get information about this
label (current value, time before expiration, etc).

It helps application to take decision for a renew
or a release of the label.

v2:
 * Add spin_lock to prevent race condition
 * return -ENOENT if no result found
 * check if flr_action is GET

v3:
 * move the spin_lock to protect only the
   relevant code
Signed-off-by: NFlorent Fourcot <florent.fourcot@enst-bretagne.fr>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

By moving code around, we avoid :

1) A reload of iph->ihl (bit field, so needs a mask)

2) A conditional test (replaced by a conditional mov on x86)
   Fast path loads iph->protocol anyway.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Tested in VLAB Works Xtensa simulation.
Signed-off-by: NBaruch Siach <baruch@tkos.co.il>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

John W. Linville says:

====================
Here is one more pull request for the 3.13 window.  This is primarily
composed of downstream pull requests that were posted while I was
traveling during the last part of the 3.12 release.

For the mac80211 bits, Johannes says:

"I have two DFS fixes (ath9k already supports DFS) and a fix for a
pointer race."

And...

"In this round for mac80211-next I have:
 * mesh channel switch support
 * a CCM rewrite, using potential hardware offloads
 * SMPS for AP mode
 * RF-kill GPIO driver updates to make it usable as an ACPI driver
 * regulatory improvements
 * documentation fixes
 * DFS for IBSS mode
 * and a few small other fixes/improvements"

For the TI driver bits, Luca says:

"Some patches intended for 3.13.  Eliad continues upstreaming pending
patches from the internal tree."

For the iwlwifi bits, Emmanuel says:

"There are a few fixes from Johannes mostly clean up patches. We have
also a few other fixes that are relevant for the new firmware that has
not been released yet."

For the Bluetooth bits, Gustavo says:

"A last fix to the 3.12. I ended forgetting to send it before, I hope we can
still make the way to 3.12. It is a revert and it fixes an issue with bluetooth
suspend/hibernate that had many bug reports. Please pull or let me know of any
problems. Thanks!"  (Obviously, that one didn't make 3.12...)

Also...

"One more big pull request for 3.13. These are the patches we queued during
last week. Here you will find a lot of improvements to the HCI and L2CAP and
MGMT layers with the main ones being a better debugfs support and end of work
of splitting L2CAP into Core and Socket parts."

Additionally, there is one ath9k patch to enable DFS in IBSS mode for
that driver.

I appreciate your consideration for taking this extra pull request
this cycle.  Please let me know if there are problems!
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next into for-davem

While testing virtio_net and skb_segment() changes, Hannes reported
that UFO was sending wrong frames.

It appears this was introduced by a recent commit :
8c3a897b ("inet: restore gso for vxlan")

The old condition to perform IP frag was :

tunnel = !!skb->encapsulation;
...
        if (!tunnel && proto == IPPROTO_UDP) {

So the new one should be :

udpfrag = !skb->encapsulation && proto == IPPROTO_UDP;
...
        if (udpfrag) {

Initialization of udpfrag must be done before call
to ops->callbacks.gso_segment(skb, features), as
skb_udp_tunnel_segment() clears skb->encapsulation

(We want udpfrag to be true for UFO, false for VXLAN)

With help from Alexei Starovoitov
Reported-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Mathias Krause says:

====================
move pskb_put (was: IPsec improvements)

This series moves pskb_put() to the core code, making the code
duplication in caif obsolete (patches 1 and 2).
Patch 3 fixes a few kernel-doc issues.

v2 of this series does no longer contain the skb_cow_data() patch and
therefore no performance improvements for IPsec. The change is still
under discussion, but otherwise independent from the above changes.

Please apply!

v2:
- kernel-doc fixes for pskb_put, as noticed by Ben
- dropped skb_cow_data patch as it's still discussed
- added a kernel-doc fixes patch (patch 3)
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use "@" to refer to parameters in the kernel-doc description. According
to Documentation/kernel-doc-nano-HOWTO.txt "&" shall be used to refer to
structures only.
Signed-off-by: NMathias Krause <mathias.krause@secunet.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Also remove the warning for fragmented packets -- skb_cow_data() will
linearize the buffer, removing all fragments.
Signed-off-by: NMathias Krause <mathias.krause@secunet.com>
Cc: Dmitry Tarnyagin <dmitry.tarnyagin@lockless.no>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This function has usage beside IPsec so move it to the core skbuff code.
While doing so, give it some documentation and change its return type to
'unsigned char *' to be in line with skb_put().
Signed-off-by: NMathias Krause <mathias.krause@secunet.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Changing MTU size of an xgmac network interface while it is active can
cause a panic like

  skbuff: skb_over_panic: text:c03bc62c len:1090 put:1090 head:edfb6900 data:edfb6942 tail:0xedfb6d84 end:0xedfb6bc0 dev:eth0
  ------------[ cut here ]------------
  kernel BUG at net/core/skbuff.c:126!
  Internal error: Oops - BUG: 0 [#1] SMP ARM
  Modules linked in:
  CPU: 0 PID: 762 Comm: python Tainted: G        W    3.10.0-00015-g3e33cd7 #309
  task: edcfe000 ti: ed67e000 task.ti: ed67e000
  PC is at skb_panic+0x64/0x70
  LR is at wake_up_klogd+0x5c/0x68

This happens because xgmac_change_mtu modifies dev->mtu before the
network interface is quiesced. And thus there still might be buffers
in use which have a buffer size based on the old MTU.

To fix this I moved the change of dev->mtu after the call to
xgmac_stop.

Another modification is required (in xgmac_stop) to ensure that
xgmac_xmit is really not called anymore (xgmac_tx_complete might wake
up the queue again).

I've tested the fix by switching MTU size every second between 600 and
1500 while network traffic was going on. The test box survived a test
of several hours (until I've stopped it) whereas w/o this fix above
panic occurs after several minutes (at most).

Change since v1:
- remove call to netif_stop_queue at beginning of xgmac_stop
- use netif_tx_disable instead of locking+netif_stop_queue
Signed-off-by: NAndreas Herrmann <andreas.herrmann@calxeda.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Amir Vadai says:

====================
net/mlx4: Mellanox driver update 07-11-2013

This patchset contains some enhancements and bug fixes for the mlx4_* drivers.
Patchset was applied and tested against commit: "9bb8ca86 virtio-net: switch to
use XPS to choose txq"
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For each RX/TX ring and its CQ, allocation is done on a NUMA node that
corresponds to the core that the data structure should operate on.
The assumption is that the core number is reflected by the ring index.
The affected allocations are the ring/CQ data structures,
the TX/RX info and the shared HW/SW buffer.
For TX rings, each core has rings of all UPs.
Signed-off-by: NYevgeny Petrilin <yevgenyp@mellanox.com>
Signed-off-by: NEugenia Emantayev <eugenia@mellanox.com>
Reviewed-by: NHadar Hen Zion <hadarh@mellanox.com>
Signed-off-by: NAmir Vadai <amirv@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is done to optimize FW/HW access to host memory.
Signed-off-by: NYevgeny Petrilin <yevgenyp@mellanox.com>
Signed-off-by: NEugenia Emantayev <eugenia@mellanox.com>
Reviewed-by: NHadar Hen Zion <hadarh@mellanox.com>
Signed-off-by: NAmir Vadai <amirv@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently all TX/RX rings and completion queues are part of the
netdev priv structure and are allocated statically. This patch
will change the priv to hold only arrays of pointers and therefore
all TX/RX rings and completetion queues will be allocated
dynamically. This is in preparation for NUMA aware allocations.
Signed-off-by: NYevgeny Petrilin <yevgenyp@mellanox.com>
Signed-off-by: NEugenia Emantayev <eugenia@mellanox.com>
Reviewed-by: NHadar Hen Zion <hadarh@mellanox.com>
Signed-off-by: NAmir Vadai <amirv@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Allow immediate activate of VGT->VST and VST->VGT transitions, without
the need of rebinding in mlx4_master_immediate_activate_vlan_qos().

Also in struct res_qp: add qp parameters (vlan_index,fvl,vlan_cntrol..)
to the saved set, in order to restore when move to VGT.
 - Clear at mlx4_RST2INIT_QP_wrapper()
 - Save at mlx4_INIT2RTR_QP_wrapper()
 - Restore at mlx4_vf_immed_vlan_work_handler()

Update mlx4_vf_immed_vlan_work_handler() to support VGT.
Signed-off-by: NRony Efraim <ronye@mellanox.com>
Signed-off-by: NJack Morgenstein <jackm@dev.mellanox.co.il>
Reviewed-by: NHadar Hen Zion <hadarh@mellanox.com>
Signed-off-by: NAmir Vadai <amirv@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

To guarantee that all unused fields in all FW commands for both inboxes
and outboxes are zeroed out, initialize the mailbox buffer to all zeroes.

This is especially important for SRIOV comm-channel virtual commands
(such as QUERY_FUNC_CAP), where if new fields are added to support new
features, the driver can depend on older kernels passing zeroes in these
fields.

In addition to zeroing out the mailbox buffer at allocation time, all
(now unnecessary) calls to memset by the callers of
mlx4_alloc_cmd_mailbox() are removed.
Signed-off-by: NMajd Dibbiny <majd@mellanox.com>
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>

Modify RFS code to support applying filters for incoming UDP streams.
Signed-off-by: NEyal Perry <eyalpe@mellanox.com>
Signed-off-by: NAmir Vadai <amirv@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

John Fastabend says:

====================
l2 hardware accelerated macvlans

This patch adds support to offload macvlan net_devices to the
hardware. With these patches packets are pushed to the macvlan
net_device directly and do not pass through the lower dev.

The patches here have made it through multiple iterations
each with a slightly different focus. First I tried to
push these as a new link type called "VMDQ". The patches
shown here,

http://comments.gmane.org/gmane.linux.network/237617

Following this implementation I renamed the link type
"VSI" and addressed various comments. Finally Neil
Horman picked up the patches and integrated the offload
into the macvlan code. Here,

http://permalink.gmane.org/gmane.linux.network/285658

The attached series is clean-up of his patches, with a
few fixes.

If folks find this series acceptable there are a few
items we can work on next. First broadcast and multicast
will use the hardware even for local traffic with this
series. It would be best (I think) to use the software
path for macvlan to macvlan traffic and save the PCIe
bus. This depends on how much you value CPU time vs
PCIE bandwidth. This will need another patch series
to flush out.

Also this series only allows for layer 2 mac forwarding
where some hardware supports more interesting forwarding
capabilities. Integrating with OVS may be useful here.

As always any comments/feedback welcome.

My basic I/O test is here but I've also done some link
testing, SRIOV/DCB with macvlans and others,

Changelog:
v2: two fixes to ixgbe when all features DCB, FCoE, SR-IOV
    are enabled with macvlans. A VMDQ_P() reference
    should have been accel->pool and do not set the offset
    of the ring index from dfwd add call. The offset is used
    by SR-IOV so clearing it can cause SR-IOV quue index's
    to go sideways. With these fixes testing macvlan's with
    SRIOV enabled was successful.
v3: addressed Neil's comments in ixgbe
    fixed error path on dfwd_add_station() in ixgbe
    fixed ixgbe to allow SRIOV and accelerated macvlans to
    coexist.
v4: Dave caught some strange indentation, fixed it here
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that l2 acceleration ops are in place from the prior patch,
enable ixgbe to take advantage of these operations.  Allow it to
allocate queues for a macvlan so that when we transmit a frame,
we can do the switching in hardware inside the ixgbe card, rather
than in software.
Signed-off-by: NJohn Fastabend <john.r.fastabend@intel.com>
Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a operations structure that allows a network interface to export
the fact that it supports package forwarding in hardware between
physical interfaces and other mac layer devices assigned to it (such
as macvlans). This operaions structure can be used by virtual mac
devices to bypass software switching so that forwarding can be done
in hardware more efficiently.
Signed-off-by: NJohn Fastabend <john.r.fastabend@intel.com>
Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

timecounter_init() was was called only after first potential
timecounter_read().
Moved mlx4_en_init_timestamp() before mlx4_en_init_netdev()
Signed-off-by: NAmir Vadai <amirv@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

"card2" is NULL here so I have changed it to use "id2" instead of
"card2->interface.id".
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There is a bug in cpsw_probe() where we do:

	ndev->irq = platform_get_irq(pdev, 0);
	if (ndev->irq < 0) {

The problem is that "ndev->irq" is unsigned so the error handling
doesn't work.  I have changed it to a regular int.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We recently added a new error path and it needs a dev_put().

Fixes: 7adac1ec ('6lowpan: Only make 6lowpan links to IEEE802154 devices')
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

On top of commit 366cddb4 "IB/rdma_cm: TOS <=> UP mapping for IBoE", add
support for case vlan egress map is used.

When the IBoE session is being set over a vlan, inherit the socket priority
to vlan priority mapping which was configured for the vlan device egress map.
Signed-off-by: NEyal Perry <eyalpe@mellanox.com>
Signed-off-by: NAmir Vadai <amirv@mellanox.com>
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Provide a method for read-only access to the vlan device egress mapping.

Do this by refactoring vlan_dev_get_egress_qos_mask() such that now it
receives as an argument the skb priority instead of pointer to the skb.

Such an access is needed for the IBoE stack where the control plane
goes through the network stack. This is an add-on step on top of commit
d4a96865 "net/route: export symbol ip_tos2prio" which allowed the RDMA-CM
to use ip_tos2prio.
Signed-off-by: NEyal Perry <eyalpe@mellanox.com>
Signed-off-by: NHadar Hen Zion <hadarh@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If build_skb fails the memory associated with the ring buffer is freed but
the ri->data member is not zeroed in this case. This causes a double-free
of this memory in tg3_free_rings->... path. The patch moves this block after
setting ri->data to NULL.
It would be nice to fix this bug also in stable >= v3.4 trees.

Cc: Nithin Nayak Sujir <nsujir@broadcom.com>
Cc: Michael Chan <mchan@broadcom.com>
Signed-off-by: NIvan Vecera <ivecera@redhat.com>
Acked-by: NMichael Chan <mchan@broadcom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Ariel Elior will take over the bnx2x maintenance.

It's been a pleasure!
Signed-off-by: NEilon Greenstein <eilong@broadcom.com>
Acked-by: NAriel Elior <ariele@broadcom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

sk_filter isn't freed if bpf_func is equal to sk_run_filter.

This memory leak was introduced by v3.12-rc3-224-gd45ed4a4
"net: fix unsafe set_memory_rw from softirq".

Before this patch sk_filter was freed in sk_filter_release_rcu,
now it should be freed in bpf_jit_free.

Here is output of kmemleak:
unreferenced object 0xffff8800b774eab0 (size 128):
  comm "systemd", pid 1, jiffies 4294669014 (age 124.062s)
  hex dump (first 32 bytes):
    00 00 00 00 0b 00 00 00 20 63 7f b7 00 88 ff ff  ........ c......
    60 d4 55 81 ff ff ff ff 30 d9 55 81 ff ff ff ff  `.U.....0.U.....
  backtrace:
    [<ffffffff816444be>] kmemleak_alloc+0x4e/0xb0
    [<ffffffff811845af>] __kmalloc+0xef/0x260
    [<ffffffff81534028>] sock_kmalloc+0x38/0x60
    [<ffffffff8155d4dd>] sk_attach_filter+0x5d/0x190
    [<ffffffff815378a1>] sock_setsockopt+0x991/0x9e0
    [<ffffffff81531bd6>] SyS_setsockopt+0xb6/0xd0
    [<ffffffff8165f3e9>] system_call_fastpath+0x16/0x1b
    [<ffffffffffffffff>] 0xffffffffffffffff

v2: add extra { } after else

Fixes: d45ed4a4 ("net: fix unsafe set_memory_rw from softirq")
Acked-by: NDaniel Borkmann <dborkman@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NAndrey Vagin <avagin@openvz.org>
Acked-by: NAlexei Starovoitov <ast@plumgrid.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Erik Hugne says:

====================
tipc: message reassembly using fragment chain

We introduce a new reassembly algorithm that improves performance
and eliminates the risk of causing out-of-memory situations.

v3: -Use skb_try_coalesce, and revert to fraglist if this does not succeed.
    -Make sure reassembly list head is uncloned.

v2: -Rebased on Ying's indentation fix.
    -Node unlock call in msg_fragmenter case moved from patch #2 to #1.
     ('continue' with this lock held would cause spinlock recursion if only
      patch #1 is used)
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If appending a received fragment to the pending fragment chain
in a unicast link fails, the current code tries to force a retransmission
of the fragment by decrementing the 'next received sequence number'
field in the link. This is done under the assumption that the failure
is caused by an out-of-memory situation, an assumption that does
not hold true after the previous patch in this series.

A failure to append a fragment can now only be caused by a protocol
violation by the sending peer, and it must hence be assumed that it
is either malicious or buggy.  Either way, the correct behavior is now
to reset the link instead of trying to revert its sequence number.
So, this is what we do in this commit.
Signed-off-by: NErik Hugne <erik.hugne@ericsson.com>
Reviewed-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When the first fragment of a long data data message is received on a link, a
reassembly buffer large enough to hold the data from this and all subsequent
fragments of the message is allocated. The payload of each new fragment is
copied into this buffer upon arrival. When the last fragment is received, the
reassembled message is delivered upwards to the port/socket layer.

Not only is this an inefficient approach, but it may also cause bursts of
reassembly failures in low memory situations. since we may fail to allocate
the necessary large buffer in the first place. Furthermore, after 100 subsequent
such failures the link will be reset, something that in reality aggravates the
situation.

To remedy this problem, this patch introduces a different approach. Instead of
allocating a big reassembly buffer, we now append the arriving fragments
to a reassembly chain on the link, and deliver the whole chain up to the
socket layer once the last fragment has been received. This is safe because
the retransmission layer of a TIPC link always delivers packets in strict
uninterrupted order, to the reassembly layer as to all other upper layers.
Hence there can never be more than one fragment chain pending reassembly at
any given time in a link, and we can trust (but still verify) that the
fragments will be chained up in the correct order.
Signed-off-by: NErik Hugne <erik.hugne@ericsson.com>
Reviewed-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a message fragment is received in a broadcast or unicast link,
the reception code will append the fragment payload to a big reassembly
buffer through a call to the function tipc_recv_fragm(). However, after
the return of that call, the logics goes on and passes the fragment
buffer to the function tipc_net_route_msg(), which will simply drop it.
This behavior is a remnant from the now obsolete multi-cluster
functionality, and has no relevance in the current code base.

Although currently harmless, this unnecessary call would be fatal
after applying the next patch in this series, which introduces
a completely new reassembly algorithm. So we change the code to
eliminate the redundant call.
Signed-off-by: NErik Hugne <erik.hugne@ericsson.com>
Reviewed-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>