There are linux distributions where the inbox bnx2x driver contains SRIOV
support but doesn't contain the changes introduced in b9871bcf
"bnx2x: VF RSS support - PF side".

A VF in a VM running that distribution over a new hypervisor will access
incorrect addresses when trying to transmit packets, causing an attention
in the hypervisor and making that VF inactive until FLRed.

The driver in the VM has to ne upgraded [no real way to overcome this], but
due to the HW attention currently arising upgrading the driver in the VM
would not suffice [since the VF needs also be FLRed if the previous driver
was already loaded].

This patch causes the PF to fail the acquire message from a VF running an
old problematic driver; The VF will then gracefully fail it's probe preventing
the HW attention [and allow clean upgrade of driver in VM].
Signed-off-by: NYuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: NAriel Elior <Ariel.Elior@qlogic.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This improves the performance of driver on machine with L1_CACHE_SHIFT of at
most 32 bytes [HW was planned for 64-byte aligned fastpath data].
Signed-off-by: NDmitry Kravkov <Dmitry.Kravkov@qlogic.com>
Signed-off-by: NYuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: NAriel Elior <Ariel.Elior@qlogic.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Until now VFs were oblvious to the actual configured link parameters.
This patch does 2 things:

  1. It enables a PF to inform its VF using the bulletin board of the link
     configured, and allows the VF to present that information.

  2. It adds support of `ndo_set_vf_link_state', allowing the hypervisor
     to set the VF link state.
Signed-off-by: NDmitry Kravkov <Dmitry.Kravkov@qlogic.com>
Signed-off-by: NYuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: NAriel Elior <Ariel.Elior@qlogic.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Jesper Dangaard Brouer says:

====================
Optimizing pktgen for single CPU performance

This series focus on optimizing "pktgen" for single CPU performance.

V2-series:
 - Removed some patches
 - Doc real reason for TX ring buffer filling up

NIC tuning for pktgen:
 http://netoptimizer.blogspot.dk/2014/06/pktgen-for-network-overload-testing.html

General overload setup according to:
 http://netoptimizer.blogspot.dk/2014/04/basic-tuning-for-network-overload.html

Hardware:
 System: CPU E5-2630
 NIC: Intel ixgbe/82599 chip

Testing done with net-next git tree on top of
 commit 6623b419 ("Merge branch 'master' of...jkirsher/net-next")

Pktgen script exercising race condition:
 https://github.com/netoptimizer/network-testing/blob/master/pktgen/unit_test01_race_add_rem_device_loop.sh

Tool for measuring LOCK overhead:
 https://github.com/netoptimizer/network-testing/blob/master/src/overhead_cmpxchg.c
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The if_lock()/if_unlock() in next_to_run() adds a significant
overhead, because its called for every packet in busy loop of
pktgen_thread_worker().  (Thomas Graf originally pointed me
at this lock problem).

Removing these two "LOCK" operations should in theory save us approx
16ns (8ns x 2), as illustrated below we do save 16ns when removing
the locks and introducing RCU protection.

Performance data with CLONE_SKB==100000, TX-size=512, rx-usecs=30:
 (single CPU performance, ixgbe 10Gbit/s, E5-2630)
 * Prev   : 5684009 pps --> 175.93ns (1/5684009*10^9)
 * RCU-fix: 6272204 pps --> 159.43ns (1/6272204*10^9)
 * Diff   : +588195 pps --> -16.50ns

To understand this RCU patch, I describe the pktgen thread model
below.

In pktgen there is several kernel threads, but there is only one CPU
running each kernel thread.  Communication with the kernel threads are
done through some thread control flags.  This allow the thread to
change data structures at a know synchronization point, see main
thread func pktgen_thread_worker().

Userspace changes are communicated through proc-file writes.  There
are three types of changes, general control changes "pgctrl"
(func:pgctrl_write), thread changes "kpktgend_X"
(func:pktgen_thread_write), and interface config changes "etcX@N"
(func:pktgen_if_write).

Userspace "pgctrl" and "thread" changes are synchronized via the mutex
pktgen_thread_lock, thus only a single userspace instance can run.
The mutex is taken while the packet generator is running, by pgctrl
"start".  Thus e.g. "add_device" cannot be invoked when pktgen is
running/started.

All "pgctrl" and all "thread" changes, except thread "add_device",
communicate via the thread control flags.  The main problem is the
exception "add_device", that modifies threads "if_list" directly.

Fortunately "add_device" cannot be invoked while pktgen is running.
But there exists a race between "rem_device_all" and "add_device"
(which normally don't occur, because "rem_device_all" waits 125ms
before returning). Background'ing "rem_device_all" and running
"add_device" immediately allow the race to occur.

The race affects the threads (list of devices) "if_list".  The if_lock
is used for protecting this "if_list".  Other readers are given
lock-free access to the list under RCU read sections.

Note, interface config changes (via proc) can occur while pktgen is
running, which worries me a bit.  I'm assuming proc_remove() takes
appropriate locks, to assure no writers exists after proc_remove()
finish.

I've been running a script exercising the race condition (leading me
to fix the proc_remove order), without any issues.  The script also
exercises concurrent proc writes, while the interface config is
getting removed.
Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
Reviewed-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Avoid calling set_current_state() inside the busy-loop in
pktgen_thread_worker().  In case of pkt_dev->delay, then it is still
used/enabled in pktgen_xmit() via the spin() call.

The set_current_state(TASK_INTERRUPTIBLE) uses a xchg, which implicit
is LOCK prefixed.  I've measured the asm LOCK operation to take approx
8ns on this E5-2630 CPU.  Performance increase corrolate with this
measurement.

Performance data with CLONE_SKB==100000, rx-usecs=30:
 (single CPU performance, ixgbe 10Gbit/s, E5-2630)
 * Prev:  5454050 pps --> 183.35ns (1/5454050*10^9)
 * Now:   5684009 pps --> 175.93ns (1/5684009*10^9)
 * Diff:  +229959 pps -->  -7.42ns
Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Using pktgen I'm seeing the ixgbe driver "push-back", due TX ring
running full.  Thus, the TX ring is artificially limiting pktgen.
(Diagnose via "ethtool -S", look for "tx_restart_queue" or "tx_busy"
counters.)

Using ixgbe, the real reason behind the TX ring running full, is due
to TX ring not being cleaned up fast enough. The ixgbe driver combines
TX+RX ring cleanups, and the cleanup interval is affected by the
ethtool --coalesce setting of parameter "rx-usecs".

Do not increase the default NIC TX ring buffer or default cleanup
interval.  Instead simply document that pktgen needs special NIC
tuning for maximum packet per sec performance.

Performance results with pktgen with clone_skb=100000.
TX ring size 512 (default), adjusting "rx-usecs":
 (Single CPU performance, E5-2630, ixgbe)
 - 3935002 pps - rx-usecs:  1 (irqs:  9346)
 - 5132350 pps - rx-usecs: 10 (irqs: 99157)
 - 5375111 pps - rx-usecs: 20 (irqs: 50154)
 - 5454050 pps - rx-usecs: 30 (irqs: 33872)
 - 5496320 pps - rx-usecs: 40 (irqs: 26197)
 - 5502510 pps - rx-usecs: 50 (irqs: 21527)

TX ring size adjusting (ethtool -G), "rx-usecs==1" (default):
 - 3935002 pps - tx-size:  512
 - 5354401 pps - tx-size:  768
 - 5356847 pps - tx-size: 1024
 - 5327595 pps - tx-size: 1536
 - 5356779 pps - tx-size: 2048
 - 5353438 pps - tx-size: 4096

Notice after commit 6f25cd47 (pktgen: fix xmit test for BQL enabled
devices) pktgen uses netif_xmit_frozen_or_drv_stopped() and ignores
the BQL "stack" pause (QUEUE_STATE_STACK_XOFF) flag.  This allow us to put
more pressure on the TX ring buffers.

It is the ixgbe_maybe_stop_tx() call that stops the transmits, and
pktgen respecting this in the call to netif_xmit_frozen_or_drv_stopped(txq).
Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This stub now allows userspace to see IFLA_INFO_KIND for ovs master and
IFLA_INFO_SLAVE_KIND for slave.
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

So far, it is assumed that ops->setup is filled up. But there might be
case that ops might make sense even without ->setup. In that case,
forbid to newlink and dellink.

This allows to register simple rtnl link ops containing only ->kind.
That allows consistent way of passing device kind (either device-kind or
slave-kind) to userspace.
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In commit 37112105("net:
QDISC_STATE_RUNNING dont need atomic bit ops") the
__QDISC_STATE_RUNNING is renamed to __QDISC___STATE_RUNNING,
but the old names existing in comment are not replaced with
the new name completely.
Signed-off-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This can be used in virtual networking applications, and
may have other uses as well.  The option is disabled by
default.

A specific use case is setting up virtual routers, bridges, and
hosts on a single OS without the use of network namespaces or
virtual machines.  With proper use of ip rules, routing tables,
veth interface pairs and/or other virtual interfaces,
and applications that can bind to interfaces and/or IP addresses,
it is possibly to create one or more virtual routers with multiple
hosts attached.  The host interfaces can act as IPv6 systems,
with radvd running on the ports in the virtual routers.  With the
option provided in this patch enabled, those hosts can now properly
obtain IPv6 addresses from the radvd.
Signed-off-by: NBen Greear <greearb@candelatech.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is disabled by default, just like similar debug info
already in this module.  But, makes it easier to find out
why RA is not being accepted when debugging strange behaviour.
Signed-off-by: NBen Greear <greearb@candelatech.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fixes build error introduced by commit 1fb6f159 (tcp: add
tcp_conn_request):

net/ipv4/tcp_input.c: In function 'pr_drop_req':
net/ipv4/tcp_input.c:5889:130: error: 'struct sock_common' has no member named 'skc_v6_daddr'
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Octavian Purdila says:

====================
tcp: remove code duplication in tcp_v[46]_conn_request

This patch series unifies the TCPv4 and TCPv6 connection request flow
in a single new function (tcp_conn_request).

The first 3 patches are small cleanups and fixes found during the code
merge process.

The next patches add new methods in tcp_request_sock_ops to abstract
the IPv4/IPv6 operations and keep the TCP connection request flow
common.

To identify potential performance issues this patch has been tested
by measuring the connection per second rate with nginx and a httperf
like client (to allow for concurrent connection requests - 256 CC were
used during testing) using the loopback interface. A dual-core i5 Ivy
Bridge processor was used and each process was bounded to a different
core to make results consistent.

Results for IPv4, unit is connections per second, higher is better, 20
measurements have been collected:

		before		after
min		27917		27962
max		28262		28366
avg		28094.1		28212.75
stdev		87.35		97.26

Results for IPv6, unit is connections per second, higher is better, 20
measurements have been collected:

		before		after
min		24813		24877
max		25029		25119
avg		24935.5		25017
stdev		64.13		62.93

Changes since v1:

 * add benchmarking datapoints

 * fix a few issues in the last patch (IPv6 related)
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Create tcp_conn_request and remove most of the code from
tcp_v4_conn_request and tcp_v6_conn_request.
Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add queue_add_hash member to tcp_request_sock_ops so that we can later
unify tcp_v4_conn_request and tcp_v6_conn_request.
Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add mss_clamp member to tcp_request_sock_ops so that we can later
unify tcp_v4_conn_request and tcp_v6_conn_request.
Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Create a new tcp_request_sock_ops method to unify the IPv4/IPv6
signature for tcp_v[46]_send_synack. This allows us to later unify
tcp_v4_rtx_synack with tcp_v6_rtx_synack and tcp_v4_conn_request with
tcp_v4_conn_request.
Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

More work in preparation of unifying tcp_v4_conn_request and
tcp_v6_conn_request: indirect the init sequence calls via the
tcp_request_sock_ops.
Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Make the tcp_v6_conn_request calls flow similar with that of
tcp_v4_conn_request.

Note that want_cookie can be true only if isn is zero and that is why
we can move the if (want_cookie) block out of the if (!isn) block.

Moving security_inet_conn_request() has a couple of side effects:
missing inet_rsk(req)->ecn_ok update and the req->cookie_ts
update. However, neither SELinux nor Smack security hooks seems to
check them. This change should also avoid future different behaviour
for IPv4 and IPv6 in the security hooks.
Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com>
Acked-by: NPaul Moore <paul@paul-moore.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Create wrappers with same signature for the IPv4/IPv6 request routing
calls and use these wrappers (via route_req method from
tcp_request_sock_ops) in tcp_v4_conn_request and tcp_v6_conn_request
with the purpose of unifying the two functions in a later patch.

We can later drop the wrapper functions and modify inet_csk_route_req
and inet6_cks_route_req to use the same signature.
Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move the specific IPv4/IPv6 cookie sequence initialization to a new
method in tcp_request_sock_ops in preparation for unifying
tcp_v4_conn_request and tcp_v6_conn_request.
Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move the specific IPv4/IPv6 intializations to a new method in
tcp_request_sock_ops in preparation for unifying tcp_v4_conn_request
and tcp_v6_conn_request.
Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since pktops is only used for IPv6 only and opts is used for IPv4
only, we can move these fields into a union and this allows us to drop
the inet6_reqsk_alloc function as after this change it becomes
equivalent with inet_reqsk_alloc.

This patch also fixes a kmemcheck issue in the IPv6 stack: the flags
field was not annotated after a request_sock was allocated.
Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 016818d0 (tcp: TCP Fast Open Server - take SYNACK RTT after
completing 3WHS) changes the code to only take a snt_synack timestamp
when a SYNACK transmit or retransmit succeeds. This behaviour is later
broken by commit 843f4a55 (tcp: use tcp_v4_send_synack on first
SYN-ACK), as snt_synack is now updated even if tcp_v4_send_synack
fails.

Also, commit 3a19ce0e (tcp: IPv6 support for fastopen server) misses
the required IPv6 updates for 016818d0.

This patch makes sure that snt_synack is updated only when the SYNACK
trasnmit/retransmit succeeds, for both IPv4 and IPv6.

Cc: Cardwell <ncardwell@google.com>
Cc: Daniel Lee <longinus00@gmail.com>
Cc: Yuchung Cheng <ycheng@google.com>
Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Jeff Kirsher says:

====================
Intel Wired LAN Driver Updates 2014-06-26

This series contains updates to i40e and i40evf.

Kamil provides a cleanup patch to i40e where we do not need to acquire the
NVM for shadow RAM checksum calculation, since we only read the shadow RAM
through SRCTL register.

Paul provides a fix for handling HMC for big endian architectures for i40e
and i40evf.

Mitch provides four cleanup and fixes for i40evf.  Fix an issue where if
the VF driver fails to complete early init, then rmmod can cause a softlock
when the driver tries to stop a watchdog timer that never got initialized.
So add a check to see if the timer is actually initialized before stopping
it.  Make the function i40evf_send_api_ver() return more useful information,
instead of just returning -EIO by propagating firmware errors back to the
caller and log a message if the PF sends an invalid reply.  Fix up a log
message that was missing a word, which makes the log message more readable.
Fix an initialization failure if many VFs are instantiated at the same time
and the VF module is autoloaded by simply resending firmware request if
there is no response the first time.

Jacob does a rename of the function i40e_ptp_enable() to
i40e_ptp_feature_enable(), like he did for ixgbe, to reduce possible
confusion and ambugity in the purpose of the function.  Does follow on
PTP work on i40e, like he did for ixgbe, by breaking the PTP hardware
control from the ioctl command for timestamping mode.  By doing this,
we can maintain state about the 1588 timestamping mode and properly
re-enable to the last known mode during a re-initialization of 1588 bits.

Anjali cleans up the i40e driver where TCP-IPv4 filters were being added
twice, which seems to be left over from when we had to add two PTYPEs for
one filter.  Fixes the flow director sideband logic to detect when there
is a full flow director table.  Also fixes the programming of FDIR where
a couple of fields in the descriptor setup that were not being
programmed, which left the opportunity for stale data to be pushed as
part of the descriptor next time it was used.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Jon Maloy says:

====================
tipc: new unicast transmission code

As a step towards making the data transmission code more maintainable
and performant, we introduce a number of new functions, both for
building, sending and rejecting messages. The new functions will
eventually be used for alla data transmission, user data unicast,
service internal messaging, and multicast/broadcast.

We start with this series, where we introduce the functions, and
let user data unicast and the internal connection protocol use them.
The remaining users will come in a later series.

There are only minor changes to data structures, and no protocol
changes, so the older functions can still be used in parallel for
some time. Until the old functions are removed, we use temporary
names for the new functions, such as tipc_build_msg2, tipc_link_xmit2.

It should be noted that the first two commits are unrelated to the
rest of the series.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As a consequence of the recently introduced serialized access
to the socket in commit 8d94168a761819d10252bab1f8de6d7b202c3baa
("tipc: same receive code path for connection protocol and data
messages") we can make a number of simplifications in the
detection and handling of connection congestion situations.

- We don't need to keep two counters, one for sent messages and one
  for acked messages. There is no longer any risk for races between
  acknowledge messages arriving in BH and data message sending
  running in user context. So we merge this into one counter,
  'sent_unacked', which is incremented at sending and subtracted
  from at acknowledge reception.

- We don't need to set the 'congested' field in tipc_port to
  true before we sent the message, and clear it when sending
  is successful. (As a matter of fact, it was never necessary;
  the field was set in link_schedule_port() before any wakeup
  could arrive anyway.)

- We keep the conditions for link congestion and connection connection
  congestion separated. There would otherwise be a risk that an arriving
  acknowledge message may wake up a user sleeping because of link
  congestion.

- We can simplify reception of acknowledge messages.

We also make some cosmetic/structural changes:

- We rename the 'congested' field to the more correct 'link_cong´.

- We rename 'conn_unacked' to 'rcv_unacked'

- We move the above mentioned fields from struct tipc_port to
  struct tipc_sock.
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Reviewed-by: NErik Hugne <erik.hugne@ericsson.com>
Reviewed-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We simplify the code for receiving connection probes, leveraging the
recently introduced tipc_msg_reverse() function. We also stick to
the principle of sending a possible response message directly from
the calling (tipc_sk_rcv or backlog_rcv) functions, hence making
the call chain shallower and easier to follow.

We make one small protocol change here, allowed according to
the spec. If a protocol message arrives from a remote socket that
is not the one we are connected to, we are currently generating a
connection abort message and send it to the source. This behavior
is unnecessary, and might even be a security risk, so instead we
now choose to only ignore the message. The consequnce for the sender
is that he will need longer time to discover his mistake (until the
next timeout), but this is an extreme corner case, and may happen
anyway under other circumstances, so we deem this change acceptable.
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Reviewed-by: NErik Hugne <erik.hugne@ericsson.com>
Reviewed-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As a preparation to eliminate port_lock we need to bring reception
of connection protocol messages under proper protection of bh_lock_sock
or socket owner.

We fix this by letting those messages follow the same code path as
incoming data messages.

As a side effect of this change, the last reference to the function
net_route_msg() disappears, and we can eliminate that function.
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Reviewed-by: NErik Hugne <erik.hugne@ericsson.com>
Reviewed-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Several functions in port.c, related to the port protocol and
connection shutdown, need to send messages. We now convert them
to use the new link send function.
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Reviewed-by: NErik Hugne <erik.hugne@ericsson.com>
Reviewed-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We move the message sending across established connections
to use the message preparation and send functions introduced
earlier in this series. We now do the message preparation
and call to the link send function directly from the socket,
instead of going via the port layer.

As a consequence of this change, the functions tipc_send(),
tipc_port_iovec_rcv(), tipc_port_iovec_reject() and tipc_reject_msg()
become unreferenced and can be eliminated from port.c. For the same
reason, the functions tipc_link_xmit_fast(), tipc_link_iovec_xmit_long()
and tipc_link_iovec_fast() can be eliminated from link.c.
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Reviewed-by: NErik Hugne <erik.hugne@ericsson.com>
Reviewed-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We merge the code for sending port name and port identity addressed
messages into the corresponding send functions in socket.c, and start
using the new fragmenting and transmit functions we just have introduced.

This saves a call level and quite a few code lines, as well as making
this part of the code easier to follow. As a consequence, the functions
tipc_send2name() and tipc_send2port() in port.c can be removed.

For practical reasons, we break out the code for sending multicast messages
from tipc_sendmsg() and move it into a separate function, tipc_sendmcast(),
but we do not yet convert it into using the new build/send functions.
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Reviewed-by: NErik Hugne <erik.hugne@ericsson.com>
Reviewed-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a message arrives in a node and finds no destination
socket, we may need to drop it, reject it, or forward it after
a secondary destination lookup. The latter two cases currently
results in a code path that is perceived as complex, because it
follows a deep call chain via obscure functions such as
net_route_named_msg() and net_route_msg().

We now introduce a function, tipc_msg_eval(), that takes the
decision about whether such a message should be rejected or
forwarded, but leaves it to the caller to actually perform
the indicated action.

If the decision is 'reject', it is still the task of the recently
introduced function tipc_msg_reverse() to take the final decision
about whether the message is rejectable or not. In the latter case
it drops the message.

As a result of this change, we can finally eliminate the function
net_route_named_msg(), and hence become independent of net_route_msg().
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Reviewed-by: NErik Hugne <erik.hugne@ericsson.com>
Reviewed-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The way we build and send rejected message is currenty perceived as
hard to follow, partly because we let the transmission go via deep
call chains through functions such as tipc_reject_msg() and
net_route_msg().

We want to remove those functions, and make the call sequences shallower
and simpler. For this purpose, we separate building and sending of
rejected messages. We build the reject message using the new function
tipc_msg_reverse(), and let the transmission go via the newly introduced
tipc_link_xmit2() function, as all transmission eventually will do. We
also ensure that all calls to tipc_link_xmit2() are made outside
port_lock/bh_lock_sock.

Finally, we replace all calls to tipc_reject_msg() with the two new
calls at all locations in the code that we want to keep. The remaining
calls are made from code that we are planning to remove, along with
tipc_reject_msg() itself.
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Reviewed-by: NErik Hugne <erik.hugne@ericsson.com>
Reviewed-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fragmentation at message sending is currently performed in two
places in link.c, depending on whether data to be transmitted
is delivered in the form of an iovec or as a big sk_buff. Those
functions are also tightly entangled with the send functions
that are using them.

We now introduce a re-entrant, standalone function, tipc_msg_build2(),
that builds a packet chain directly from an iovec. Each fragment is
sized according to the MTU value given by the caller, and is prepended
with a correctly built fragment header, when needed. The function is
independent from who is calling and where the chain will be delivered,
as long as the caller is able to indicate a correct MTU.

The function is tested, but not called by anybody yet. Since it is
incompatible with the existing tipc_msg_build(), and we cannot yet
remove that function, we have given it a temporary name.
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Reviewed-by: NErik Hugne <erik.hugne@ericsson.com>
Reviewed-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Message fragmentation is currently performed at link level, inside
the protection of node_lock. This potentially binds up the sending
link structure for a long time, instead of letting it do other tasks,
such as handle reception of new packets.

In this commit, we make the MTUs of each active link become easily
accessible from the socket level, i.e., without taking any spinlock
or dereferencing the target link pointer. This way, we make it possible
to perform fragmentation in the sending socket, before sending the
whole fragment chain to the link for transport.
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Reviewed-by: NErik Hugne <erik.hugne@ericsson.com>
Reviewed-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The current link implementation provides several different transmit
functions, depending on the characteristics of the message to be
sent: if it is an iovec or an sk_buff, if it needs fragmentation or
not, if the caller holds the node_lock or not. The permutation of
these options gives us an unwanted amount of unnecessarily complex
code.

As a first step towards simplifying the send path for all messages,
we introduce two new send functions at link level, tipc_link_xmit2()
and __tipc_link_xmit2(). The former looks up a link to the message
destination, and if one is found, it grabs the node lock and calls
the second function, which works exclusively inside the node lock
protection. If no link is found, and the destination is on the same
node, it delivers the message directly to the local destination
socket.

The new functions take a buffer chain where all packet headers are
already prepared, and the correct MTU has been used. These two
functions will later replace all other link-level transmit functions.

The functions are not backwards compatible, so we have added them
as new functions with temporary names. They are tested, but have no
users yet. Those will be added later in this series.
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Reviewed-by: NErik Hugne <erik.hugne@ericsson.com>
Reviewed-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>