After device is stopped we reset the rings by moving all free buffers
to positions [0, cnt - 2], and clear the position cnt - 1 in the ring.
We then proceed to clear the read/write pointers.  This means that if
we try to reset the ring again the code will assume that the next to
fill buffer is at position 0 and swap it with cnt - 1.  Since we
previously cleared position cnt - 1 it will lead to leaking the first
buffer and leaving ring in a bad state.

This scenario can only happen if FW communication fails, in which case
the ring will never be used again, so the fact it's in a bad state will
not be noticed.  Buffer leak is the only problem.  Don't try to move
buffers in the ring if the read/write pointers indicate the ring was
never used or have already been reset.

nfp_net_clear_config_and_disable() is now fully idempotent.

Found by code inspection, FW communication failures are very rare,
and reconfiguring a live device is not common either, so it's unlikely
anyone has ever noticed the leak.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Now that we have offload replay infrastructure added by
commit 32636742 ("net: sched: call reoffload op on block callback reg")
and flows are guaranteed to be removed correctly, we can revert
commit 951a8ee6 ("nfp: reject binding to shared blocks").
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: John Hurley <john.hurley@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Commit f599c64f ("xen-netfront: Fix race between device setup and
open") changed the initialization order: xennet_create_queues() now
happens before we do register_netdev() so using netdev->name in
xennet_init_queue() is incorrect, we end up with the following in
/proc/interrupts:

 60:        139          0   xen-dyn    -event     eth%d-q0-tx
 61:        265          0   xen-dyn    -event     eth%d-q0-rx
 62:        234          0   xen-dyn    -event     eth%d-q1-tx
 63:          1          0   xen-dyn    -event     eth%d-q1-rx

and this looks ugly. Actually, using early netdev name (even when it's
already set) is also not ideal: nowadays we tend to rename eth devices
and queue name may end up not corresponding to the netdev name.

Use nodename from xenbus device for queue naming: this can't change in VM's
lifetime. Now /proc/interrupts looks like

 62:        202          0   xen-dyn    -event     device/vif/0-q0-tx
 63:        317          0   xen-dyn    -event     device/vif/0-q0-rx
 64:        262          0   xen-dyn    -event     device/vif/0-q1-tx
 65:         17          0   xen-dyn    -event     device/vif/0-q1-rx

Fixes: f599c64f ("xen-netfront: Fix race between device setup and open")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add MODULE_LICENSE() to net/dsa/realtek.o to fix build warning message.

WARNING: modpost: missing MODULE_LICENSE() in drivers/net/dsa/realtek.o
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

As was recently discussed [1], let's avoid casting the const buf in
bonding_sysfs_store_option and use kstrndup/kfree instead.

[1] http://lists.openwall.net/netdev/2018/07/22/25Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Jason Wang says:

====================
TX used ring batched updating for vhost

This series implement batch updating of used ring for TX. This help to
reduce the cache contention on used ring. The idea is first split
datacopy path from zerocopy, and do only batching for datacopy. This
is because zercopy had already supported its own batching.

TX PPS was increased 25.8% and Netperf TCP does not show obvious
differences.

The split of datapath will also be helpful for future implementation
like in order completion.
====================
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Like commit e2b3b35e ("vhost_net: batch used ring update in rx"),
this patches implements batch used ring update for datacopy TX
(zerocopy has already done some kind of batching).

Testpmd transmission from guest to host (XDP_DROP on tap) shows 25.8%
improvement (from ~3.1Mpps to ~3.9Mpps) on Broadwell i7-5600U CPU @
2.60GHz machine. Netperf TCP tests does not show obvious differences.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

A more generic name which could be used for TX as well.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Rename for reusing this for TX.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Instead of mixing zerocopy and datacopy logics, this patch tries to
split datacopy logic out. This results for a more compact code and
ad-hoc optimization could be done on top more easily.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Introduce tx_can_batch() to determine whether TX could be
batched. This will help to reduce the code duplication in the future.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Factor out logic of getting tx buffer and iov iter
initialization. This will be used for reducing codes duplication in
the future.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Introduce init_iov_iter() in order to be reused by future patch.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Remove the mode parameter for igmp/igmp6_group_added as we can get it
from first parameter.

Fixes: 6e2059b5 (ipv4/igmp: init group mode as INCLUDE when join source group)
Fixes: c7ea20c9 (ipv6/mcast: init as INCLUDE when join SSM INCLUDE group)
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Moved end of comment to it's own line per guide
Signed-off-by: Mark Railton <mark@markrailton.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

"imply HWMON" was supposed to ensure that the SFP phy code can be built
with HWMON enabled or disabled while at the same time ensuring that
HWMON is not built as module if SFP is built into the kernel.
Unfortunately, that does not work as intended. With "allmodconfig", it
results in several unrelated HWMON drivers to be disabled instead of
being built as module as expected.

Let's use the old "depends on HWMON || HWMON=n" instead. This is slightly
different (it enforces SFP to be built as module if HWMON is built as
module), but it is better than the alternative of using "IS_REACHABLE()"
in the driver since that would disable sensor support if HWMON is built
as module and SFP is built into the kernel.

Fixes: 1323061a ("net: phy: sfp: Add HWMON support for module sensors")
Cc: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

Use vzalloc instead of the vmalloc, memset combo
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Use dma_zalloc_coherent instead of dma_alloc_coherent
followed by memset 0.
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fixes the following sparse warnings:

net/tipc/link.c:376:5: warning: symbol 'link_bc_rcv_gap' was not declared. Should it be static?
net/tipc/link.c:823:6: warning: symbol 'link_prepare_wakeup' was not declared. Should it be static?
net/tipc/link.c:959:6: warning: symbol 'tipc_link_advance_backlog' was not declared. Should it be static?
net/tipc/link.c:1009:5: warning: symbol 'tipc_link_retrans' was not declared. Should it be static?
net/tipc/monitor.c:687:5: warning: symbol '__tipc_nl_add_monitor_peer' was not declared. Should it be static?
net/tipc/group.c:230:20: warning: symbol 'tipc_group_find_member' was not declared. Should it be static?
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This line makes up what macro PTR_ERR_OR_ZERO already does. So,
make use of PTR_ERR_OR_ZERO rather than an open-code version.

This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Jon Maxwell says:

====================
tcp: improve setsockopt() TCP_USER_TIMEOUT accuracy

The patch was becoming bigger based on feedback therefore I have
implemented a series of 3 commits instead in V4.

This series is a continuation based on V3 here and associated feedback:

https://patchwork.kernel.org/patch/10516195/

Suggestions by Neal Cardwell:

1) Fix up units mismatch regarding msec/jiffies.
2) Address possiblility of time_remaining being negative.
3) Add a helper routine tcp_clamp_rto_to_user_timeout() to do the rto
calculation.
4) Move start_ts logic into helper routine tcp_retrans_stamp() to
validate tcp_sk(sk)->retrans_stamp.
5) Some u32 declation and return refactoring.
6) Return 0 instead of false in tcp_retransmit_stamp(), it's not a bool.

Suggestions by David Laight:

1) Don't cache rto in tcp_clamp_rto_to_user_timeout().

Suggestions by Eric Dumazet:

1) Make u32 declartions consistent.
2) Use patch series for easier review.
3) Convert icsk->icsk_user_timeout to millisconds to avoid jiffie to
msec dance.
4) Use seperate titles for each commit in the series.
5) Fix fuzzy indentation and line wrap issues.
6) Make commit titles descriptive.

Changes:

1) Call tcp_clamp_rto_to_user_timeout(sk) as an argument to
inet_csk_reset_xmit_timer() to save on rto declaration.

Every time the TCP retransmission timer fires. It checks to see if
there is a timeout before scheduling the next retransmit timer. The
retransmit interval between each retransmission increases
exponentially. The issue is that in order for the timeout to occur the
retransmit timer needs to fire again. If the user timeout check happens
after the 9th retransmit for example. It needs to wait for the 10th
retransmit timer to fire in order to evaluate whether a timeout has
occurred or not. If the interval is large enough then the timeout will
be inaccurate.

For example with a TCP_USER_TIMEOUT of 10 seconds without patch:

1st retransmit:

22:25:18.973488 IP host1.49310 > host2.search-agent: Flags [.]

Last retransmit:

22:25:26.205499 IP host1.49310 > host2.search-agent: Flags [.]

Timeout:

send: Connection timed out
Sun Jul  1 22:25:34 EDT 2018

We can see that last retransmit took ~7 seconds. Which pushed the total
timeout to ~15 seconds instead of the expected 10 seconds. This gets
more inaccurate the larger the TCP_USER_TIMEOUT value. As the interval
increases.

Add tcp_clamp_rto_to_user_timeout() to determine if the user rto has
expired. Or whether the rto interval needs to be recalculated. Use the
original interval if user rto is not set.

Test results with the patch is the expected 10 second timeout:

1st retransmit:

01:37:59.022555 IP host1.49310 > host2.search-agent: Flags [.]

Last retransmit:

01:38:06.486558 IP host1.49310 > host2.search-agent: Flags [.]

Timeout:

send: Connection timed out
Mon Jul  2 01:38:09 EDT 2018
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Create the tcp_clamp_rto_to_user_timeout() helper routine. To calculate
the correct rto, so that the TCP_USER_TIMEOUT socket option is more
accurate. Taking suggestions and feedback into account from
Eric Dumazet, Neal Cardwell and David Laight. Due to the 1st commit we
can avoid the msecs_to_jiffies() and jiffies_to_msecs() dance.
Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Create a seperate helper routine as per Neal Cardwells suggestion. To
be used by the final commit in this series and retransmits_timed_out().
Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This is a preparatory commit. Part of this series that improves the
socket TCP_USER_TIMEOUT option accuracy. Implement Eric Dumazets idea
to convert icsk->icsk_user_timeout from jiffies to msecs. To eliminate
the msecs_to_jiffies() and jiffies_to_msecs() dance in future.
Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Julian Wiedmann says:

====================
s390/qeth: updates 2018-07-19

please apply one more round of qeth patches to net-next.
This brings additional performance improvements for the transmit code,
and some refactoring to pave the way for using netdev_priv.
Also, two minor fixes for rare corner cases.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Modify the L2 OSA xmit path so that it also supports L2 IQD devices
(in particular, their HW header requirements). This allows IQD devices
to advertise NETIF_F_SG support, and eliminates the allocation overhead
for the HW header.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Some transmit modes require that the HW header is located in the same
page as the initial protocol headers in skb->data. Let callers specify
the size of this contiguous header range, and enforce it when building
the HW header.

While at it, apply some gentle renaming to the relevant L2 code so that
it matches the L3 code.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When checking whether an skb needs to be linearized to fit into an IO
buffer, it's desirable to consider the skb's final size and layout
(ie. after the HW header was added). But a subsequent linearization can
then cause the re-positioned HW header to violate its alignment
restrictions.

Dealing with this situation in two different code paths is quite tricky.
This patch integrates a) linearize-check and b) HW header construction
into one 3 step-sequence:
1. evaluate how the HW header needs to be added (to identify if it takes
   up an additional buffer element), then
2. check if the required buffer elements exceed the device's limit.
   Linearize when necessary and re-evaluate the HW header placement.
3. Add the HW header in the best-possible way:
   a) push, without taking up an additional buffer element
   b) push, but consume another buffer element
   c) allocate a header object from the cache.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Nowadays an skb fragment typically spans over multiple pages. So replace
the obsolete, SG-only 'fragments' counter with one that tracks the
consumed buffer elements. This is what actually matters for performance.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

qeth's ndo_change_mtu() only applies some trivial bounds checking. Set
up dev->min_mtu properly, so that dev_set_mtu() can do this for us.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When the MPC initialization code discovers the HW-specific max MTU,
apply the resulting changes straight to the netdevice.

If this is the device's first initialization, also set its MTU
(HiperSockets: the max MTU; else: a layer-specific default value).
Then cap the current MTU by the new max MTU.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The netdevice is always available now, so get the portno from there.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Allocation of the netdevice is currently delayed until a qeth card first
goes online. This complicates matters in several places, where we need
to cache values instead of applying them straight to the netdevice.

Improve on this by moving the allocation up to where the qeth card
itself is created. This is also one step in direction of eventually
placing the qeth card into netdev_priv().

In all subsequent code, remove the now redundant checks whether
card->dev is valid.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netif_carrier_off() does its own checking.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

After the subdriver's remove() routine has completed, the card's layer
mode is undetermined again. Reflect this in the layer2 field.

If qeth_dev_layer2_store() hits an error after remove() was called, the
card _always_ requires a setup(), even if the previous layer mode is
requested again.
But qeth_dev_layer2_store() bails out early if the requested layer mode
still matches the current one. So unless we reset the layer2 field,
re-probing the card back to its previous mode is currently not possible.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

By updating q->used_buffers only _after_ do_QDIO() has completed, there
is a potential race against the buffer's TX completion. In the unlikely
case that the TX completion path wins, qeth_qdio_output_handler() would
decrement the counter before qeth_flush_buffers() even incremented it.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Salil Mehta says:

====================
Misc. cleanups for HNS3 ethernet driver

This patch-set presents some cleanups for HNS3 Ethernet Driver.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Add the SPDX identifiers to HNS3 PF driver.
Signed-off-by: Jian Shen <shenjian15@huawei.com>
Signed-off-by: Peng Li <lipeng321@huawei.com>
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>