This patch adds the minimum necessary for the RTAX_CC_ALGO congestion
control metric to be set up and dumped back to user space.

While the internal representation of RTAX_CC_ALGO is handled as a u32
key, we avoided to expose this implementation detail to user space, thus
instead, we chose the netlink attribute that is being exchanged between
user space to be the actual congestion control algorithm name, similarly
as in the setsockopt(2) API in order to allow for maximum flexibility,
even for 3rd party modules.

It is a bit unfortunate that RTAX_QUICKACK used up a whole RTAX slot as
it should have been stored in RTAX_FEATURES instead, we first thought
about reusing it for the congestion control key, but it brings more
complications and/or confusion than worth it.

Joint work with Florian Westphal.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

fib_nh_match does not match nexthops correctly. Example:

ip route add 172.16.10/24 nexthop via 192.168.122.12 dev eth0 \
                          nexthop via 192.168.122.13 dev eth0
ip route del 172.16.10/24 nexthop via 192.168.122.14 dev eth0 \
                          nexthop via 192.168.122.15 dev eth0

Del command is successful and route is removed. After this patch
applied, the route is correctly matched and result is:
RTNETLINK answers: No such process

Please consider this for stable trees as well.

Fixes: 4e902c57 ("[IPv4]: FIB configuration using struct fib_config")
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

nh_exceptions is effectively used under rcu, but lacks proper
barriers. Between kzalloc() and setting of nh->nh_exceptions(),
we need a proper memory barrier.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Fixes: 4895c771 ("ipv4: Add FIB nexthop exceptions.")
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Increment fib_info_cnt in fib_create_info() right after successfuly
alllocating fib_info structure, overwise fib_metrics allocation failure
leads to fib_info_cnt incorrectly decremented in free_fib_info(), called
on error path from fib_create_info().
Signed-off-by: NSergey Popovich <popovich_sergei@mail.ru>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As suggested by Julian:

	Simply, flowi4_iif must not contain 0, it does not
	look logical to ignore all ip rules with specified iif.

because in fib_rule_match() we do:

        if (rule->iifindex && (rule->iifindex != fl->flowi_iif))
                goto out;

flowi4_iif should be LOOPBACK_IFINDEX by default.

We need to move LOOPBACK_IFINDEX to include/net/flow.h:

1) It is mostly used by flowi_iif

2) Fix the following compile error if we use it in flow.h
by the patches latter:

In file included from include/linux/netfilter.h:277:0,
                 from include/net/netns/netfilter.h:5,
                 from include/net/net_namespace.h:21,
                 from include/linux/netdevice.h:43,
                 from include/linux/icmpv6.h:12,
                 from include/linux/ipv6.h:61,
                 from include/net/ipv6.h:16,
                 from include/linux/sunrpc/clnt.h:27,
                 from include/linux/nfs_fs.h:30,
                 from init/do_mounts.c:32:
include/net/flow.h: In function ‘flowi4_init_output’:
include/net/flow.h:84:32: error: ‘LOOPBACK_IFINDEX’ undeclared (first use in this function)

Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Julian Anastasov <ja@ssi.bg>
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>

Make fib_detect_death function static only used in one file.
Signed-off-by: NStephen Hemminger <stephen@networkplumber.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The rtmsg_fib function doesn't modify this argument so mark
it const.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit d2d68ba9 (ipv4: Cache input routes in fib_info nexthops)
assmued that "locally destined, and routed packets, never trigger
PMTU events or redirects that will be processed by us".

However, it seems that tunnel devices do trigger PMTU events in certain
cases. At least ip_gre, ip6_gre, sit, and ipip do use the inner flow's
skb_dst(skb)->ops->update_pmtu to propage mtu information from the
outer flows. These can cause the inner flow mtu to be decreased. If
next hop exceptions are not consulted for pmtu, IP fragmentation will
not be done properly for these routes.

It also seems that we really need to have the PMTU information always
for netfilter TCPMSS clamp-to-pmtu feature to work properly.

So for the time being, cache separate copies of input routes for
each next hop exception.
Signed-off-by: NTimo Teräs <timo.teras@iki.fi>
Reviewed-by: NJulian Anastasov <ja@ssi.bg>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

I'm not sure why, but the hlist for each entry iterators were conceived

        list_for_each_entry(pos, head, member)

The hlist ones were greedy and wanted an extra parameter:

        hlist_for_each_entry(tpos, pos, head, member)

Why did they need an extra pos parameter? I'm not quite sure. Not only
they don't really need it, it also prevents the iterator from looking
exactly like the list iterator, which is unfortunate.

Besides the semantic patch, there was some manual work required:

 - Fix up the actual hlist iterators in linux/list.h
 - Fix up the declaration of other iterators based on the hlist ones.
 - A very small amount of places were using the 'node' parameter, this
 was modified to use 'obj->member' instead.
 - Coccinelle didn't handle the hlist_for_each_entry_safe iterator
 properly, so those had to be fixed up manually.

The semantic patch which is mostly the work of Peter Senna Tschudin is here:

@@
iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host;

type T;
expression a,c,d,e;
identifier b;
statement S;
@@

-T b;
    <+... when != b
(
hlist_for_each_entry(a,
- b,
c, d) S
|
hlist_for_each_entry_continue(a,
- b,
c) S
|
hlist_for_each_entry_from(a,
- b,
c) S
|
hlist_for_each_entry_rcu(a,
- b,
c, d) S
|
hlist_for_each_entry_rcu_bh(a,
- b,
c, d) S
|
hlist_for_each_entry_continue_rcu_bh(a,
- b,
c) S
|
for_each_busy_worker(a, c,
- b,
d) S
|
ax25_uid_for_each(a,
- b,
c) S
|
ax25_for_each(a,
- b,
c) S
|
inet_bind_bucket_for_each(a,
- b,
c) S
|
sctp_for_each_hentry(a,
- b,
c) S
|
sk_for_each(a,
- b,
c) S
|
sk_for_each_rcu(a,
- b,
c) S
|
sk_for_each_from
-(a, b)
+(a)
S
+ sk_for_each_from(a) S
|
sk_for_each_safe(a,
- b,
c, d) S
|
sk_for_each_bound(a,
- b,
c) S
|
hlist_for_each_entry_safe(a,
- b,
c, d, e) S
|
hlist_for_each_entry_continue_rcu(a,
- b,
c) S
|
nr_neigh_for_each(a,
- b,
c) S
|
nr_neigh_for_each_safe(a,
- b,
c, d) S
|
nr_node_for_each(a,
- b,
c) S
|
nr_node_for_each_safe(a,
- b,
c, d) S
|
- for_each_gfn_sp(a, c, d, b) S
+ for_each_gfn_sp(a, c, d) S
|
- for_each_gfn_indirect_valid_sp(a, c, d, b) S
+ for_each_gfn_indirect_valid_sp(a, c, d) S
|
for_each_host(a,
- b,
c) S
|
for_each_host_safe(a,
- b,
c, d) S
|
for_each_mesh_entry(a,
- b,
c, d) S
)
    ...+>

[akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c]
[akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c]
[akpm@linux-foundation.org: checkpatch fixes]
[akpm@linux-foundation.org: fix warnings]
[akpm@linux-foudnation.org: redo intrusive kvm changes]
Tested-by: NPeter Senna Tschudin <peter.senna@gmail.com>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NSasha Levin <sasha.levin@oracle.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

A small host typically needs ~10 fib_info structures, so create initial
hash table with 16 slots instead of only one. This removes potential
false sharing and reallocs/rehashes (1->2->4->8->16)
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Avoid checking nh_pcpu_rth_output in fast path,
abort fib_info creation on alloc_percpu failure.
Signed-off-by: NJulian Anastasov <ja@ssi.bg>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit d2d68ba9 (ipv4: Cache input routes in fib_info nexthops.)
introduced a regression for forwarding.

This was hard to reproduce but the symptom was that packets were
delivered to local host instead of being forwarded.

David suggested to add fib_type to fib_info so that we dont
inadvertently share same fib_info for different purposes.

With help from Julian Anastasov who provided very helpful
hints, reproduced here :

<quote>
        Can it be a problem related to fib_info reuse
from different routes. For example, when local IP address
is created for subnet we have:

broadcast 192.168.0.255 dev DEV  proto kernel  scope link  src
192.168.0.1
192.168.0.0/24 dev DEV  proto kernel  scope link  src 192.168.0.1
local 192.168.0.1 dev DEV  proto kernel  scope host  src 192.168.0.1

        The "dev DEV  proto kernel  scope link  src 192.168.0.1" is
a reused fib_info structure where we put cached routes.
The result can be same fib_info for 192.168.0.255 and
192.168.0.0/24. RTN_BROADCAST is cached only for input
routes. Incoming broadcast to 192.168.0.255 can be cached
and can cause problems for traffic forwarded to 192.168.0.0/24.
So, this patch should solve the problem because it
separates the broadcast from unicast traffic.

        And the ip_route_input_slow caching will work for
local and broadcast input routes (above routes 1 and 3) just
because they differ in scope and use different fib_info.

</quote>

Many thanks to Chris Clayton for his patience and help.
Reported-by: NChris Clayton <chris2553@googlemail.com>
Bisected-by: NChris Clayton <chris2553@googlemail.com>
Reported-by: NDave Jones <davej@redhat.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Julian Anastasov <ja@ssi.bg>
Tested-by: NChris Clayton <chris2553@googlemail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It is a frequent mistake to confuse the netlink port identifier with a
process identifier.  Try to reduce this confusion by renaming fields
that hold port identifiers portid instead of pid.

I have carefully avoided changing the structures exported to
userspace to avoid changing the userspace API.

I have successfully built an allyesconfig kernel with this change.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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

Input path is mostly run under RCU and doesnt touch dst refcnt

But output path on forwarding or UDP workloads hits
badly dst refcount, and we have lot of false sharing, for example
in ipv4_mtu() when reading rt->rt_pmtu

Using a percpu cache for nh_rth_output gives a nice performance
increase at a small cost.

24 udpflood test on my 24 cpu machine (dummy0 output device)
(each process sends 1.000.000 udp frames, 24 processes are started)

before : 5.24 s
after : 2.06 s
For reference, time on linux-3.5 : 6.60 s
Signed-off-by: NEric Dumazet <edumazet@google.com>
Tested-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit 404e0a8b (net: ipv4: fix RCU races on dst refcounts) tried
to solve a race but added a problem at device/fib dismantle time :

We really want to call dst_free() as soon as possible, even if sockets
still have dst in their cache.
dst_release() calls in free_fib_info_rcu() are not welcomed.

Root of the problem was that now we also cache output routes (in
nh_rth_output), we must use call_rcu() instead of call_rcu_bh() in
rt_free(), because output route lookups are done in process context.

Based on feedback and initial patch from David Miller (adding another
call_rcu_bh() call in fib, but it appears it was not the right fix)

I left the inet_sk_rx_dst_set() helper and added __rcu attributes
to nh_rth_output and nh_rth_input to better document what is going on in
this code.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit c6cffba4 (ipv4: Fix input route performance regression.)
added various fatal races with dst refcounts.

crashes happen on tcp workloads if routes are added/deleted at the same
time.

The dst_free() calls from free_fib_info_rcu() are clearly racy.

We need instead regular dst refcounting (dst_release()) and make
sure dst_release() is aware of RCU grace periods :

Add DST_RCU_FREE flag so that dst_release() respects an RCU grace period
before dst destruction for cached dst

Introduce a new inet_sk_rx_dst_set() helper, using atomic_inc_not_zero()
to make sure we dont increase a zero refcount (On a dst currently
waiting an rcu grace period before destruction)

rt_cache_route() must take a reference on the new cached route, and
release it if was not able to install it.

With this patch, my machines survive various benchmarks.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

With the routing cache removal we lost the "noref" code paths on
input, and this can kill some routing workloads.

Reinstate the noref path when we hit a cached route in the FIB
nexthops.

With help from Eric Dumazet.
Reported-by: NAlexander Duyck <alexander.duyck@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Caching input routes is slightly simpler than output routes, since we
don't need to be concerned with nexthop exceptions.  (locally
destined, and routed packets, never trigger PMTU events or redirects
that will be processed by us).

However, we have to elide caching for the DIRECTSRC and non-zero itag
cases.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If we have an output route that lacks nexthop exceptions, we can cache
it in the FIB info nexthop.

Such routes will have DST_HOST cleared because such routes refer to a
family of destinations, rather than just one.

The sequence of the handling of exceptions during route lookup is
adjusted to make the logic work properly.

Before we allocate the route, we lookup the exception.

Then we know if we will cache this route or not, and therefore whether
DST_HOST should be set on the allocated route.

Then we use DST_HOST to key off whether we should store the resulting
route, during rt_set_nexthop(), in the FIB nexthop cache.

With help from Eric Dumazet.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

free_nh_exceptions() should use rcu_dereference_protected(..., 1)
since its called after one RCU grace period.

Also add some const-ification in recent code.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In a regime where we have subnetted route entries, we need a way to
store persistent storage about destination specific learned values
such as redirects and PMTU values.

This is implemented here via nexthop exceptions.

The initial implementation is a 2048 entry hash table with relaiming
starting at chain length 5.  A more sophisticated scheme can be
devised if that proves necessary.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Rather than at every struct rtable creation.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If the user hasn't actually installed any custom rules, or fiddled
with the default ones, don't go through the whole FIB rules layer.

It's just pure overhead.

Instead do what we do with CONFIG_IP_MULTIPLE_TABLES disabled, check
the individual tables by hand, one by one.

Also, move fib_num_tclassid_users into the ipv4 network namespace.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If rpfilter is off (or the SKB has an IPSEC path) and there are not
tclassid users, we don't have to do anything at all when
fib_validate_source() is invoked besides setting the itag to zero.

We monitor tclassid uses with a counter (modified only under RTNL and
marked __read_mostly) and we protect the fib_validate_source() real
work with a test against this counter and whether rpfilter is to be
done.

Having a way to know whether we need no tclassid processing or not
also opens the door for future optimized rpfilter algorithms that do
not perform full FIB lookups.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It makes no sense to execute this limit test every time we create a
routing cache entry.

We can't simply error out on these things since we've silently
accepted and truncated them forever.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We hit a kernel OOPS.

<3>[23898.789643] BUG: sleeping function called from invalid context at
/data/buildbot/workdir/ics/hardware/intel/linux-2.6/arch/x86/mm/fault.c:1103
<3>[23898.862215] in_atomic(): 0, irqs_disabled(): 0, pid: 10526, name:
Thread-6683
<4>[23898.967805] HSU serial 0000:00:05.1: 0000:00:05.2:HSU serial prevented me
to suspend...
<4>[23899.258526] Pid: 10526, comm: Thread-6683 Tainted: G        W
3.0.8-137685-ge7742f9 #1
<4>[23899.357404] HSU serial 0000:00:05.1: 0000:00:05.2:HSU serial prevented me
to suspend...
<4>[23899.904225] Call Trace:
<4>[23899.989209]  [<c1227f50>] ? pgtable_bad+0x130/0x130
<4>[23900.000416]  [<c1238c2a>] __might_sleep+0x10a/0x110
<4>[23900.007357]  [<c1228021>] do_page_fault+0xd1/0x3c0
<4>[23900.013764]  [<c18e9ba9>] ? restore_all+0xf/0xf
<4>[23900.024024]  [<c17c007b>] ? napi_complete+0x8b/0x690
<4>[23900.029297]  [<c1227f50>] ? pgtable_bad+0x130/0x130
<4>[23900.123739]  [<c1227f50>] ? pgtable_bad+0x130/0x130
<4>[23900.128955]  [<c18ea0c3>] error_code+0x5f/0x64
<4>[23900.133466]  [<c1227f50>] ? pgtable_bad+0x130/0x130
<4>[23900.138450]  [<c17f6298>] ? __ip_route_output_key+0x698/0x7c0
<4>[23900.144312]  [<c17f5f8d>] ? __ip_route_output_key+0x38d/0x7c0
<4>[23900.150730]  [<c17f63df>] ip_route_output_flow+0x1f/0x60
<4>[23900.156261]  [<c181de58>] ip4_datagram_connect+0x188/0x2b0
<4>[23900.161960]  [<c18e981f>] ? _raw_spin_unlock_bh+0x1f/0x30
<4>[23900.167834]  [<c18298d6>] inet_dgram_connect+0x36/0x80
<4>[23900.173224]  [<c14f9e88>] ? _copy_from_user+0x48/0x140
<4>[23900.178817]  [<c17ab9da>] sys_connect+0x9a/0xd0
<4>[23900.183538]  [<c132e93c>] ? alloc_file+0xdc/0x240
<4>[23900.189111]  [<c123925d>] ? sub_preempt_count+0x3d/0x50

Function free_fib_info resets nexthop_nh->nh_dev to NULL before releasing
fi. Other cpu might be accessing fi. Fixing it by delaying the releasing.

With the patch, we ran MTBF testing on Android mobile for 12 hours
and didn't trigger the issue.

Thank Eric for very detailed review/checking the issue.
Signed-off-by: NYanmin Zhang <yanmin_zhang@linux.intel.com>
Signed-off-by: NKun Jiang <kunx.jiang@intel.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These macros contain a hidden goto, and are thus extremely error
prone and make code hard to audit.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove all #inclusions of asm/system.h preparatory to splitting and killing
it.  Performed with the following command:

perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *`
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Use a more current kernel messaging style.

Convert a printk block to print_hex_dump.
Coalesce formats, align arguments.
Use %s, __func__ instead of embedding function names.

Some messages that were prefixed with <foo>_close are
now prefixed with <foo>_fini.  Some ah4 and esp messages
are now not prefixed with "ip ".

The intent of this patch is to later add something like
  #define pr_fmt(fmt) "IPv4: " fmt.
to standardize the output messages.

Text size is trivially reduced. (x86-32 allyesconfig)

$ size net/ipv4/built-in.o*
   text	   data	    bss	    dec	    hex	filename
 887888	  31558	 249696	1169142	 11d6f6	net/ipv4/built-in.o.new
 887934	  31558	 249800	1169292	 11d78c	net/ipv4/built-in.o.old
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 4670994d(net,rcu: convert call_rcu(fc_rport_free_rcu) to
kfree_rcu()) introduced a memory leak. This patch reverts it.
Signed-off-by: NZheng Yan <zheng.z.yan@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The rcu callback fc_rport_free_rcu() just calls a kfree(),
so we use kfree_rcu() instead of the call_rcu(fc_rport_free_rcu).
Signed-off-by: NLai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

Move the scope value out of the fib alias entries and into fib_info,
so that we always use the correct scope when recomputing the nexthop
cached source address.
Reported-by: NJulian Anastasov <ja@ssi.bg>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Any operation that:

1) Brings up an interface
2) Adds an IP address to an interface
3) Deletes an IP address from an interface

can potentially invalidate the nh_saddr value, requiring
it to be recomputed.

Perform the recomputation lazily using a generation ID.
Reported-by: NJulian Anastasov <ja@ssi.bg>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Alessandro Suardi reported that we could not change route metrics :

ip ro change default .... advmss 1400

This regression came with commit 9c150e82 (Allocate fib metrics
dynamically). fib_metrics is no longer an array, but a pointer to an
array.
Reported-by: NAlessandro Suardi <alessandro.suardi@gmail.com>
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Tested-by: NAlessandro Suardi <alessandro.suardi@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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

To start doing these conversions, we need to add some temporary
flow4_* macros which will eventually go away when all the protocol
code paths are changed to work on AF specific flowi objects.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

I intend to turn struct flowi into a union of AF specific flowi
structs.  There will be a common structure that each variant includes
first, much like struct sock_common.

This is the first step to move in that direction.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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

We have to use cfg->fc_scope not the final nh_scope value.
Reported-by: NJulian Anastasov <ja@ssi.bg>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>