Now fundamentally we can process lists of SKBs as cheaply
as single packets.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Just maintain the list properly by returning the head of the remaining
SKB list from dev_hard_start_xmit().
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

dev_hard_start_xmit() does two things, it first validates and
canonicalizes the SKB, then it actually sends it.

Make a set of helper functions for doing the first part.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For now it will always be false.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There is a slight policy change happening here as well.

The previous code would drop the entire rest of the GSO skb if any of
them got, for example, a congestion notification.

That makes no sense, anything NET_XMIT_MASK and below is something
like congestion or policing.  And in the congestion case it doesn't
even mean the packet was actually dropped.

Just continue until dev_xmit_complete() evaluates to false.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Hopefully making the code a bit easier to read and digest.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

That way we don't have to audit every call site to make sure it is
doing this properly.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Allow GRO path to "consume" checksums provided in CHECKSUM_UNNECESSARY
and to report new checksums verfied for use in fallback to normal
path.

Change GRO checksum path to track csum_level using a csum_cnt field
in NAPI_GRO_CB. On GRO initialization, if ip_summed is
CHECKSUM_UNNECESSARY set NAPI_GRO_CB(skb)->csum_cnt to
skb->csum_level + 1. For each checksum verified, decrement
NAPI_GRO_CB(skb)->csum_cnt while its greater than zero. If a checksum
is verfied and NAPI_GRO_CB(skb)->csum_cnt == 0, we have verified a
deeper checksum than originally indicated in skbuf so increment
csum_level (or initialize to CHECKSUM_UNNECESSARY if ip_summed is
CHECKSUM_NONE or CHECKSUM_COMPLETE).
Signed-off-by: NTom Herbert <therbert@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add skb_gro_checksum_validate, skb_gro_checksum_validate_zero_check,
and skb_gro_checksum_simple_validate, and __skb_gro_checksum_complete.
These are the cognates of the normal checksum functions but are used
in the gro_receive path and operate on GRO related fields in sk_buffs.
Signed-off-by: NTom Herbert <therbert@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Replace open codings of (((u64) <x> * <y>) >> 32) with reciprocal_scale().
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently the functionality to untag traffic on input resides
as part of the vlan module and is build only when VLAN support
is enabled in the kernel.  When VLAN is disabled, the function
vlan_untag() turns into a stub and doesn't really untag the
packets.  This seems to create an interesting interaction
between VMs supporting checksum offloading and some network drivers.

There are some drivers that do not allow the user to change
tx-vlan-offload feature of the driver.  These drivers also seem
to assume that any VLAN-tagged traffic they transmit will
have the vlan information in the vlan_tci and not in the vlan
header already in the skb.  When transmitting skbs that already
have tagged data with partial checksum set, the checksum doesn't
appear to be updated correctly by the card thus resulting in a
failure to establish TCP connections.

The following is a packet trace taken on the receiver where a
sender is a VM with a VLAN configued.  The host VM is running on
doest not have VLAN support and the outging interface on the
host is tg3:
10:12:43.503055 52:54:00:ae:42:3f > 28:d2:44:7d:c2:de, ethertype 802.1Q
(0x8100), length 78: vlan 100, p 0, ethertype IPv4, (tos 0x0, ttl 64, id 27243,
offset 0, flags [DF], proto TCP (6), length 60)
    10.0.100.1.58545 > 10.0.100.10.ircu-2: Flags [S], cksum 0xdc39 (incorrect
-> 0x48d9), seq 1069378582, win 29200, options [mss 1460,sackOK,TS val
4294837885 ecr 0,nop,wscale 7], length 0
10:12:44.505556 52:54:00:ae:42:3f > 28:d2:44:7d:c2:de, ethertype 802.1Q
(0x8100), length 78: vlan 100, p 0, ethertype IPv4, (tos 0x0, ttl 64, id 27244,
offset 0, flags [DF], proto TCP (6), length 60)
    10.0.100.1.58545 > 10.0.100.10.ircu-2: Flags [S], cksum 0xdc39 (incorrect
-> 0x44ee), seq 1069378582, win 29200, options [mss 1460,sackOK,TS val
4294838888 ecr 0,nop,wscale 7], length 0

This connection finally times out.

I've only access to the TG3 hardware in this configuration thus have
only tested this with TG3 driver.  There are a lot of other drivers
that do not permit user changes to vlan acceleration features, and
I don't know if they all suffere from a similar issue.

The patch attempt to fix this another way.  It moves the vlan header
stipping code out of the vlan module and always builds it into the
kernel network core.  This way, even if vlan is not supported on
a virtualizatoin host, the virtual machines running on top of such
host will still work with VLANs enabled.

CC: Patrick McHardy <kaber@trash.net>
CC: Nithin Nayak Sujir <nsujir@broadcom.com>
CC: Michael Chan <mchan@broadcom.com>
CC: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: NVladislav Yasevich <vyasevic@redhat.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Kernel transmit latency is often incurred in the packet scheduler.
Introduce a new timestamp on transmission just before entering the
scheduler. When data travels through multiple devices (bonding,
tunneling, ...) each device will export an individual timestamp.
Signed-off-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

No need for the unlikely(), WARN_ON() and BUG_ON() internally use
unlikely() on the condition.
Signed-off-by: NThomas Graf <tgraf@suug.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently it's done silently (from the kernel part), and thus it might be
hard to track the renames from logs.

Add a simple netdev_info() to notify the rename, but only in case the
previous name was valid.

CC: "David S. Miller" <davem@davemloft.net>
CC: Eric Dumazet <edumazet@google.com>
CC: Vlad Yasevich <vyasevic@redhat.com>
CC: stephen hemminger <stephen@networkplumber.org>
CC: Jerry Chu <hkchu@google.com>
CC: Ben Hutchings <bhutchings@solarflare.com>
CC: David Laight <David.Laight@ACULAB.COM>
Signed-off-by: NVeaceslav Falico <vfalico@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This way we'll always know in what status the device is, unless it's
running normally (i.e. NETDEV_REGISTERED).

Also, emit a warning once in case of a bad reg_state.

CC: "David S. Miller" <davem@davemloft.net>
CC: Jason Baron <jbaron@akamai.com>
CC: Eric Dumazet <edumazet@google.com>
CC: Vlad Yasevich <vyasevic@redhat.com>
CC: stephen hemminger <stephen@networkplumber.org>
CC: Jerry Chu <hkchu@google.com>
CC: Ben Hutchings <bhutchings@solarflare.com>
CC: Joe Perches <joe@perches.com>
Signed-off-by: NVeaceslav Falico <vfalico@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NFrancois Romieu <romieu@fr.zoreil.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fixed a bug that was introduced by my GRE-GRO patch
(bf5a755f net-gre-gro: Add GRE
support to the GRO stack) that breaks the forwarding path
because various GSO related fields were not set. The bug will
cause on the egress path either the GSO code to fail, or a
GRE-TSO capable (NETIF_F_GSO_GRE) NICs to choke. The following
fix has been tested for both cases.
Signed-off-by: NH.K. Jerry Chu <hkchu@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Extend alloc_netdev{,_mq{,s}}() to take name_assign_type as argument, and convert
all users to pass NET_NAME_UNKNOWN.

Coccinelle patch:

@@
expression sizeof_priv, name, setup, txqs, rxqs, count;
@@

(
-alloc_netdev_mqs(sizeof_priv, name, setup, txqs, rxqs)
+alloc_netdev_mqs(sizeof_priv, name, NET_NAME_UNKNOWN, setup, txqs, rxqs)
|
-alloc_netdev_mq(sizeof_priv, name, setup, count)
+alloc_netdev_mq(sizeof_priv, name, NET_NAME_UNKNOWN, setup, count)
|
-alloc_netdev(sizeof_priv, name, setup)
+alloc_netdev(sizeof_priv, name, NET_NAME_UNKNOWN, setup)
)

v9: move comments here from the wrong commit
Signed-off-by: NTom Gundersen <teg@jklm.no>
Reviewed-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Based on a patch from David Herrmann.

This is the only place devices can be renamed.

v9: restore revers-christmas-tree order of local variables
Signed-off-by: NTom Gundersen <teg@jklm.no>
Reviewed-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A bug was introduced in NETDEV_CHANGE notifier sequence causing the
arp table to be sometimes spuriously cleared (including manual arp
entries marked permanent), upon network link carrier changes.

The changed argument for the notifier was applied only to a single
caller of NETDEV_CHANGE, missing among others netdev_state_change().
So upon net_carrier events induced by the network, which are
triggering a call to netdev_state_change(), arp_netdev_event() would
decide whether to clear or not arp cache based on random/junk stack
values (a kind of read buffer overflow).

Fixes: be9efd36 ("net: pass changed flags along with NETDEV_CHANGE event")
Fixes: 6c8b4e3f ("arp: flush arp cache on IFF_NOARP change")
Signed-off-by: NLoic Prylli <loicp@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In process_backlog the input_pkt_queue is only checked once for new
packets and quota is artificially reduced to reflect precisely the
number of packets on the input_pkt_queue so that the loop exits
appropriately.

This patches changes the behavior to be more straightforward and
less convoluted. Packets are processed until either the quota
is met or there are no more packets to process.

This patch seems to provide a small, but noticeable performance
improvement. The performance improvement is a result of staying
in the process_backlog loop longer which can reduce number of IPI's.

Performance data using super_netperf TCP_RR with 200 flows:

Before fix:

88.06% CPU utilization
125/190/309 90/95/99% latencies
1.46808e+06 tps
1145382 intrs.sec.

With fix:

87.73% CPU utilization
122/183/296 90/95/99% latencies
1.4921e+06 tps
1021674.30 intrs./sec.
Signed-off-by: NTom Herbert <therbert@google.com>
Acked-by: NEric Dumazet <edumazet@google.com>
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>

In __dev_open(), it already calls dev_set_rx_mode().
and dev_set_rx_mode() has no effect for a net device which does not have
IFF_UP flag set.

So the call of dev_set_rx_mode() is duplicate in __dev_change_flags().
Signed-off-by: NWeiping Pan <panweiping3@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

unregister_netdevice_many() API is error prone and we had too
many bugs because of dangling LIST_HEAD on stacks.

See commit f87e6f47 ("net: dont leave active on stack LIST_HEAD")

In fact, instead of making sure no caller leaves an active list_head,
just force a list_del() in the callee. No one seems to need to access
the list after unregister_netdevice_many()
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If an MPLS packet requires segmentation then use mpls_features
to determine if the software implementation should be used.

As no driver advertises MPLS GSO segmentation this will always be
the case.

I had not noticed that this was necessary before as software MPLS GSO
segmentation was already being used in my test environment. I believe that
the reason for that is the skbs in question always had fragments and the
driver I used does not advertise NETIF_F_FRAGLIST (which seems to be the
case for most drivers). Thus software segmentation was activated by
skb_gso_ok().

This introduces the overhead of an extra call to skb_network_protocol()
in the case where where CONFIG_NET_MPLS_GSO is set and
skb->ip_summed == CHECKSUM_NONE.

Thanks to Jesse Gross for prompting me to investigate this.
Signed-off-by: NSimon Horman <horms@verge.net.au>
Acked-by: NYAMAMOTO Takashi <yamamoto@valinux.co.jp>
Acked-by: NThomas Graf <tgraf@suug.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It is available since v3.15-rc5.

Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When we jump to free_pcpu on failure in alloc_netdev_mqs()
rx and tx queues are not yet allocated, so no need to free them.

Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

After 1e785f48 ("net: Start with correct mac_len in
skb_network_protocol") skb->mac_len is used as a start of the
calculation in skb_network_protocol() but that is not always correct. If
skb->protocol == 8021Q/AD, usually the vlan header is already inserted
in the skb (i.e. vlan reorder hdr == 0). Usually when the packet enters
dev_hard_xmit it has mac_len == 0 so we take 2 bytes from the
destination mac address (skb->data + VLAN_HLEN) as a type in
skb_network_protocol() and return vlan_depth == 4. In the case where TSO is
off, then the mac_len is set but it's == 18 (ETH_HLEN + VLAN_HLEN), so
skb_network_protocol() returns a type from inside the packet and
offset == 22. Also make vlan_depth unsigned as suggested before.
As suggested by Eric Dumazet, move the while() loop in the if() so we
can avoid additional testing in fast path.

Here are few netperf tests + debug printk's to illustrate:
cat netperf.tso-on.reorder-on.bugged
- Vlan -> device (reorder on, default, this case is okay)
MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to
192.168.3.1 () port 0 AF_INET
Recv   Send    Send
Socket Socket  Message  Elapsed
Size   Size    Size     Time     Throughput
bytes  bytes   bytes    secs.    10^6bits/sec

 87380  16384  16384    10.00    7111.54
[   81.605435] skb->len 65226 skb->gso_size 1448 skb->proto 0x800
skb->mac_len 0 vlan_depth 0 type 0x800

- Vlan -> device (reorder off, bad)
cat netperf.tso-on.reorder-off.bugged
MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to
192.168.3.1 () port 0 AF_INET
Recv   Send    Send
Socket Socket  Message  Elapsed
Size   Size    Size     Time     Throughput
bytes  bytes   bytes    secs.    10^6bits/sec

 87380  16384  16384    10.00     241.35
[  204.578332] skb->len 1518 skb->gso_size 0 skb->proto 0x8100
skb->mac_len 0 vlan_depth 4 type 0x5301
0x5301 are the last two bytes of the destination mac.

And if we stop TSO, we may get even the following:
[   83.343156] skb->len 2966 skb->gso_size 1448 skb->proto 0x8100
skb->mac_len 18 vlan_depth 22 type 0xb84
Because mac_len already accounts for VLAN_HLEN.

After the fix:
cat netperf.tso-on.reorder-off.fixed
MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to
192.168.3.1 () port 0 AF_INET
Recv   Send    Send
Socket Socket  Message  Elapsed
Size   Size    Size     Time     Throughput
bytes  bytes   bytes    secs.    10^6bits/sec

 87380  16384  16384    10.01    5001.46
[   81.888489] skb->len 65230 skb->gso_size 1448 skb->proto 0x8100
skb->mac_len 0 vlan_depth 18 type 0x800

CC: Vlad Yasevich <vyasevic@redhat.com>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: Daniel Borkman <dborkman@redhat.com>
CC: David S. Miller <davem@davemloft.net>

Fixes:1e785f48 ("net: Start with correct mac_len in
skb_network_protocol")
Signed-off-by: NNikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Prior to commit fbd929f2
	bonding: support QinQ for bond arp interval

the arp monitoring code allowed for proper detection of devices
stacked on top of vlans.  Since the above commit, the
code can still detect a device stacked on top of single
vlan, but not a device stacked on top of Q-in-Q configuration.
The search will only set the inner vlan tag if the route
device is the vlan device.  However, this is not always the
case, as it is possible to extend the stacked configuration.

With this patch it is possible to provision devices on
top Q-in-Q vlan configuration that should be used as
a source of ARP monitoring information.

For example:
ip link add link bond0 vlan10 type vlan proto 802.1q id 10
ip link add link vlan10 vlan100 type vlan proto 802.1q id 100
ip link add link vlan100 type macvlan

Note:  This patch limites the number of stacked VLANs to 2,
just like before.  The original, however had another issue
in that if we had more then 2 levels of VLANs, we would end
up generating incorrectly tagged traffic.  This is no longer
possible.

Fixes: fbd929f2 (bonding: support QinQ for bond arp interval)
CC: Jay Vosburgh <j.vosburgh@gmail.com>
CC: Veaceslav Falico <vfalico@redhat.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: Ding Tianhong <dingtianhong@huawei.com>
CC: Patric McHardy <kaber@trash.net>
Signed-off-by: NVlad Yasevich <vyasevic@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts commit dc8eaaa0.
	vlan: Fix lockdep warning when vlan dev handle notification

Instead we use the new new API to find the lock subclass of
our vlan device.  This way we can support configurations where
vlans are interspersed with other devices:
  bond -> vlan -> macvlan -> vlan
Signed-off-by: NVlad Yasevich <vyasevic@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Multiple devices in the kernel can be stacked/nested and they
need to know their nesting level for the purposes of lockdep.
This patch provides a generic function that determines a nesting
level of a particular device by its type (ex: vlan, macvlan, etc).
We only care about nesting of the same type of devices.

For example:
  eth0 <- vlan0.10 <- macvlan0 <- vlan1.20

The nesting level of vlan1.20 would be 1, since there is another vlan
in the stack under it.
Signed-off-by: NVlad Yasevich <vyasevic@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Starting from linux-3.13, GRO attempts to build full size skbs.

Problem is the commit assumed one particular field in skb->cb[]
was clean, but it is not the case on some stacked devices.

Timo reported a crash in case traffic is decrypted before
reaching a GRE device.

Fix this by initializing NAPI_GRO_CB(skb)->last at the right place,
this also removes one conditional.

Thanks a lot to Timo for providing full reports and bisecting this.

Fixes: 8a29111c ("net: gro: allow to build full sized skb")
Bisected-by: NTimo Teras <timo.teras@iki.fi>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Tested-by: NTimo Teräs <timo.teras@iki.fi>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

From: Cong Wang <cwang@twopensource.com>

commit 50624c93 (net: Delay default_device_exit_batch until no
devices are unregistering) introduced rtnl_lock_unregistering() for
default_device_exit_batch(). Same race could happen we when rmmod a driver
which calls rtnl_link_unregister() as we call dev->destructor without rtnl
lock.

For long term, I think we should clean up the mess of netdev_run_todo()
and net namespce exit code.

Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NCong Wang <cwang@twopensource.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts commit d2069403,
there are no more callers.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fixes ordering of rtnl notifications during unregister_netdevice
by moving RTM_DELLINK notification to until after ndo_uninit.

The problem was seen with unregistering bond netdevices.

bond ndo_uninit callback generates a few RTM_NEWLINK notifications for
NETDEV_CHANGEADDR and NETDEV_FEAT_CHANGE. This is seen mostly when the
bond is deleted with slaves still enslaved to the bond.

During unregister netdevice (rollback_registered_many to be specific)
bond ndo_uninit is called after RTM_DELLINK notification goes out.
This results in userspace seeing RTM_DELLINK followed by a couple of
RTM_NEWLINK's.

In userspace problem was seen with libnl. libnl cache deletes the bond
when it sees RTM_DELLINK and re-adds the bond with the following
RTM_NEWLINK. Resulting in a stale bond entry in libnl cache when the kernel
has already deleted the bond.

This patch has been tested for bond, bridges and vlan devices.
Signed-off-by: NRoopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds the helper __dev_forward_skb which is identical to
dev_forward_skb except that it doesn't actually inject the skb into
the stack.  This is useful where we wish to have finer control over
how the packet is injected, e.g., via netif_rx_ni or netif_receive_skb.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>