rocker_port_fdb_flush() is called by rocker_port_stp_update() which in
turn may be called with trans == SWITCHDEV_TRANS_PREPARE and then
trans == SWITCHDEV_TRANS_COMMIT from switchdev_port_attr_set() via
br_set_state().

When rocker_port_fdb_flush() is called with trans == SWITCHDEV_TRANS_PREPARE
it calls rocker_port_fdb_learn() for each entry in the FDB table which in
turn calls rocker_flow_tbl_bridge() which will allocate memory using
rocker_port_kzalloc(). rocker_port_fdb_learn() will then remove the entry
from the FDB table.

Then when rocker_port_fdb_learn() is called with
trans == SWITCHDEV_TRANS_PREPARE no calls are made to rocker_port_fdb_learn()
because there are no longer any entries present in the FDB table. Thus the
memory previously allocated by rocker_port_fdb_learn() is leaked resulting
in the kernel BUG() below.

Furthermore, it looks like the driver ends up with an incorrect view of the
fdb table as the FDB entries are purged from the driver's table but not the
hardware's table.

ip link add br0 type bridge
ip link set up dev eth0
sleep 1
ip link set dev eth0 master br0
[    3.704360] ------------[ cut here ]------------
[    3.704611] kernel BUG at drivers/net/ethernet/rocker/rocker.c:4289!
[    3.704962] invalid opcode: 0000 [#1] SMP
[    3.705537] Modules linked in:
[    3.705919] CPU: 0 PID: 63 Comm: ip Not tainted 4.1.0-rc3-01046-gb9fbe709 #1044
[    3.706191] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.0-0-g4c59f5d-20150219_092859-nilsson.home.kraxel.org 04/01/2014
[    3.706820] task: ffff880019f70150 ti: ffff88001f92c000 task.ti: ffff88001f92c000
[    3.707138] RIP: 0010:[<ffffffff811f0080>]  [<ffffffff811f0080>] rocker_port_attr_set+0xe0/0xf0
[    3.707990] RSP: 0018:ffff88001f92f808  EFLAGS: 00000212
[    3.708200] RAX: ffff880019d4fa68 RBX: ffff880019d4f000 RCX: 0000000000000000
[    3.708471] RDX: 000000000000000c RSI: ffff88001f92f890 RDI: ffff880019d4f680
[    3.708740] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000004
[    3.708999] R10: ffff880000034024 R11: 0000000000000000 R12: ffff88001f92f890
[    3.709276] R13: ffff88001f8f1c00 R14: 000000000000000b R15: 0000000000000000
[    3.709303] FS:  00007f8ab66bd700(0000) GS:ffff88001b000000(0000) knlGS:0000000000000000
[    3.709303] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    3.709303] CR2: 0000000000654988 CR3: 000000001f8f3000 CR4: 00000000000006b0
[    3.709303] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[    3.709303] DR3: 0000000000000000 DR6: 0000000000000000 DR7: 0000000000000000
[    3.709303] Stack:
[    3.709303]  ffff88001f8f1c00 000000000000000b ffff88001f92f890 ffff880019d4f000
[    3.709303]  ffff88001f92f890 ffffffff813332f5 ffff88001f92f880 0000000000000000
[    3.709303]  ffff88001f92f890 0000000000000001 ffff880019d4f000 ffffffff81333627
[    3.709303] Call Trace:
[    3.709303]  [<ffffffff813332f5>] ? __switchdev_port_attr_set+0x25/0x90
[    3.709303]  [<ffffffff81333627>] ? switchdev_port_attr_set+0x27/0x120
[    3.709303]  [<ffffffff81318e86>] ? br_set_state+0x36/0x50
[    3.709303]  [<ffffffff8131795c>] ? br_add_if+0x37c/0x400
[    3.709303]  [<ffffffff81238ce1>] ? do_setlink+0x7e1/0x800
[    3.709303]  [<ffffffff8111f980>] ? radix_tree_lookup_slot+0x10/0x30
[    3.709303]  [<ffffffff81136fba>] ? nla_parse+0xaa/0x110
[    3.709303]  [<ffffffff81239c98>] ? rtnl_newlink+0x548/0x870
[    3.709303]  [<ffffffff8111f900>] ? __radix_tree_lookup+0x40/0xb0
[    3.709303]  [<ffffffff81136f3e>] ? nla_parse+0x2e/0x110
[    3.709303]  [<ffffffff81237d7e>] ? rtnetlink_rcv_msg+0x7e/0x250
[    3.709303]  [<ffffffff8121d1be>] ? __skb_recv_datagram+0xfe/0x4b0
[    3.709303]  [<ffffffff81237d00>] ? rtnetlink_rcv+0x30/0x30
[    3.709303]  [<ffffffff81247948>] ? netlink_rcv_skb+0xa8/0xd0
[    3.709303]  [<ffffffff81237cef>] ? rtnetlink_rcv+0x1f/0x30
[    3.709303]  [<ffffffff81247210>] ? netlink_unicast+0x150/0x200
[    3.709303]  [<ffffffff81247704>] ? netlink_sendmsg+0x374/0x3e0
[    3.709303]  [<ffffffff8120f8cf>] ? sock_sendmsg+0xf/0x30
[    3.709303]  [<ffffffff8120ffc3>] ? ___sys_sendmsg+0x1f3/0x200
[    3.709303]  [<ffffffff812100d5>] ? ___sys_recvmsg+0x105/0x140
[    3.709303]  [<ffffffff812228d9>] ? dev_get_by_name_rcu+0x69/0x90
[    3.709303]  [<ffffffff812228d9>] ? dev_get_by_name_rcu+0x69/0x90
[    3.709303]  [<ffffffff81217b7d>] ? skb_dequeue+0x4d/0x60
[    3.709303]  [<ffffffff81217bb0>] ? skb_queue_purge+0x20/0x30
[    3.709303]  [<ffffffff810ebdcf>] ? __inode_wait_for_writeback+0x5f/0xb0
[    3.709303]  [<ffffffff810648b0>] ? autoremove_wake_function+0x30/0x30
[    3.709303]  [<ffffffff81210ee9>] ? __sys_sendmsg+0x39/0x70
[    3.709303]  [<ffffffff8133e097>] ? system_call_fastpath+0x12/0x6a
[    3.709303] Code: bb 90 06 00 00 48 c7 04 24 00 00 00 00 45 31 c9 45 31 c0 48 c7 c1 c0 b7 1e 81 89 ea e8 da da ff ff eb 95 0f 1f 84 00 00 00 00 00 <0f> 0b 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 48 83 fe 15 75
[    3.709303] RIP  [<ffffffff811f0080>] rocker_port_attr_set+0xe0/0xf0
[    3.709303]  RSP <ffff88001f92f808>
[    3.721409] ---[ end trace b7481fcb7cb032aa ]---
Segmentation fault

Fixes: c4f20321 ("rocker: support prepare-commit transaction model")
Acked-by: NScott Feldman <sfeldma@gmail.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NSimon Horman <simon.horman@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

- introduce port fdb obj and generic switchdev_port_fdb_add/del/dump()
- use switchdev_port_fdb_add/del/dump in rocker/team/bonding ndo ops.
- add support for fdb obj in switchdev_port_obj_add/del/dump()
- switch rocker to implement fdb ops via switchdev_ops

v3: updated to sync with named union changes.
Signed-off-by: NSridhar Samudrala <sridhar.samudrala@intel.com>
Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Once we get a neighbour through looking up arp cache or creating a
new one in rocker_port_ipv4_resolve(), the neighbour's refcount is
already taken. But as we don't put the refcount again after it's
used, this makes the neighbour entry leaked.
Suggested-by: NEric Dumazet <edumazet@google.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NYing Xue <ying.xue@windriver.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Older gcc versions (e.g.  gcc version 4.4.6) don't like anonymous unions
which was causing build issues on the newly added switchdev attr/obj
structs.  Fix this by using named union on structs.
Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Reported-by: NOr Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

And let driver convert it to host-byte order as needed.
Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Well almost clean: ignore the CHECKs for space after cast operator and some
longer-than-80 char cases where for readability it's better to keep as-is.
Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Roopa said remove the feature flag for this series and she'll work on
bringing it back if needed at a later date.
Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The IPv4 FIB ops convert nicely to the switchdev objs and we're left with
only four switchdev ops: port get/set and port add/del.  Other objs will
follow, such as FDB.  So go ahead and convert IPv4 FIB over to switchdev
obj for consistency, anticipating more objs to come.
Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Rocker, bonding and team and switch over to the new
switchdev_port_bridge_dellink to avoid duplicating code in each driver.
Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Rocker, bonding, and team can now use the switchdev bridge setlink to parse
raw netlink; no need to duplicate this code in each driver.
Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

rocker: use switchdev get/set attr for bridge port flags
Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

STP update is just a settable port attribute, so convert
switchdev_port_stp_update to an attr set.

For DSA, the prepare phase is skipped and STP updates are only done in the
commit phase.  This is because currently the DSA drivers don't need to
allocate any memory for STP updates and the STP update will not fail to HW
(unless something horrible goes wrong on the MDIO bus, in which case the
prepare phase wouldn't have been able to predict anyway).
Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For rocker, support prepare-commit transaction model for setting attributes
(and for adding objects).  This requires rocker to preallocate memory
needed for the commit up front in the prepare phase.  Since rtnl_lock is
held between prepare-commit, store the allocated memory on a queue hanging
off of the rocker_port.  Also, in prepare phase, do everything right up to
calling into HW.  The same code paths are tranversed in the driver for both
prepare and commit phases.  In some cases, any state modified in the
prepare phase must be reverted before returning so the commit phase makes
the same decisions.

As a consequence of holding rtnl_lock in process context for all attr sets
(and obj adds), all memory is GFP_KERNEL allocated and we don't need to
busy spin waiting for the device to complete the command.  So the bulk of
this patch is simplifying the memory allocations to only use GFP_KERNEL and
to remove the nowait flag and busy spin loop.
Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Switch ID is just a gettable port attribute.  Convert switchdev op
switchdev_parent_id_get to a switchdev attr.

Note: for sysfs and netlink interfaces, SWITCHDEV_ATTR_PORT_PARENT_ID is
called with SWITCHDEV_F_NO_RECUSE to limit switch ID user-visiblity to only
port netdevs.  So when a port is stacked under bond/bridge, the user can
only query switch id via the switch ports, but not via the upper devices
Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Turned out that "switchdev" sticks. So just unify all related terms to use
this prefix.
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Acked-by: NRoopa Prabhu <roopa@cumulusnetworks.com>
Acked-by: NAndy Gospodarek <gospo@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Turned out that "switchdev" sticks. So just unify all related terms to use
this prefix.
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Acked-by: NRoopa Prabhu <roopa@cumulusnetworks.com>
Acked-by: NAndy Gospodarek <gospo@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A small cleanup to make use of the ether_addr_equal helper.
Signed-off-by: NSimon Horman <simon.horman@netronome.com>
Acked-by: NScott Feldman <sfeldma@gmail.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

NLM_F_MULTI must be used only when a NLMSG_DONE message is sent. In fact,
it is sent only at the end of a dump.

Libraries like libnl will wait forever for NLMSG_DONE.

Fixes: e5a55a89 ("net: create generic bridge ops")
Fixes: 815cccbf ("ixgbe: add setlink, getlink support to ixgbe and ixgbevf")
CC: John Fastabend <john.r.fastabend@intel.com>
CC: Sathya Perla <sathya.perla@emulex.com>
CC: Subbu Seetharaman <subbu.seetharaman@emulex.com>
CC: Ajit Khaparde <ajit.khaparde@emulex.com>
CC: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
CC: intel-wired-lan@lists.osuosl.org
CC: Jiri Pirko <jiri@resnulli.us>
CC: Scott Feldman <sfeldma@gmail.com>
CC: Stephen Hemminger <stephen@networkplumber.org>
CC: bridge@lists.linux-foundation.org
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix to return -EINVAL from the invalid PCI region size error
handling case instead of 0, as done elsewhere in this function.
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Master change notifications may occur other than when joining or
leaving a bridge, for example when being added to or removed from
a bond or Open vSwitch.

Previously in those cases rocker_port_bridge_leave() was called
which results in a null-pointer dereference as rocker_port->bridge_dev
is NULL because there is no bridge device.

This patch makes provision for doing nothing in such cases.

Fixes: 6c707945 ("rocker: implement L2 bridge offloading")
Acked-by: NJiri Pirko <jiri@resnulli.us>
Acked-by: NScott Feldman <sfeldma@gmail.com>
Signed-off-by: NSimon Horman <simon.horman@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Implement the phys_port_name operation. Port names are pulled from the
rocker hardware model in qemu and default to the qemu name + port id.
e.g.,

sw1p1: flags=4098<BROADCAST,MULTICAST>  mtu 1500
        ether 52:54:00:12:35:01  txqueuelen 1000  (Ethernet)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 0  bytes 0 (0.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

where 'sw1' comes from the qemu command line -device rocker,name=sw1, and
'p1' is port 1.

Patch is adapted from Scott's phys_port_id patch.
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Acked-by: NScott Feldman <sfeldma@gmail.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In hast to fix some sparse warning, I hard-coded a fix-sized array on the stack
which is probably too big for kernel standards.  Fix this by converting array
to dynamic allocation.
Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move swdev wrappers over to new swdev ops (from previous ndo ops).  No
functional changes to the implementation.
Signed-off-by: NScott Feldman <sfeldma@gmail.com>

rocker: move to new swdev ops
Signed-off-by: NScott Feldman <sfeldma@gmail.com>

dsa: move to new swdev ops
Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pass in the netlink flags (NLM_F_*) into switchdev driver for IPv4 FIB add op
to allow driver to 1) optimize hardware updates, 2) handle ip route prepend
and append commands correctly.
Suggested-by: NJamal Hadi Salim <jhs@mojatatu.com>
Suggested-by: NRoopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Acked-by: NRoopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Reviewed-by: NJonathan Toppins <jtoppins@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver implements ndo_switch_fib_ipv4_add/del ops to add/del/mod IPv4
routes to/from switchdev device.  Once a route is added to the device, and the
route's nexthops are resolved to neighbor MAC address, the device will forward
matching pkts rather than the kernel.  This offloads the L3 forwarding path
from the kernel to the device.  Note that control and management planes are
still mananged by Linux; only the data plane is offloaded.  Standard routing
control protocols such as OSPF and BGP run on Linux and manage the kernel's FIB
via standard rtm netlink msgs...nothing changes here.

A new hash table is added to rocker to track neighbors.  The driver listens for
neighbor updates events using netevent notifier NETEVENT_NEIGH_UPDATE.  Any ARP
table updates for ports on this device are recorded in this table.  Routes
installed to the device with nexthops that reference neighbors in this table
are "qualified".  In the case of a route with nexthops not resolved in the
table, the kernel is asked to resolve the nexthop.

The driver uses fib_info->fib_priority for the priority field in rocker's
unicast routing table.

The device can only forward to pkts matching route dst to resolved nexthops.
Currently, the device only supports single-path routes (i.e. routes with one
nexthop).  Equal Cost Multipath (ECMP) route support will be added in followup
patches.

This patch is driver support for unicast IPv4 routing only.  Followup patches
will add driver and infrastructure for IPv6 routing and multicast routing.
Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

"val" is declared as a u64 so static checkers complain that this shift
can wrap.  I don't have the hardware but probably it's doesn't have over
31 ports.  Still we may as well silence the warning even if it's not a
real bug.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Acked-by: NScott Feldman <sfeldma@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Make sure kmalloc() succeeds.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Acked-by: NScott Feldman <sfeldma@gmail.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Cleanup the port forwarding state transitions for the cases when the port
joins or leaves a bridge, or is brought admin UP or DOWN.  When port is
bridged, we can rely on bridge driver putting port in correct state using
STP callback into port driver, regardless if bridge is enabled for STP or not.
When port is not bridged, we can reuse some of the STP code to enabled or
disable forwarding depending on UP or DOWN.

Tested by trying all the transitions from bridge/not bridge, and UP/DOWN, and
verifying port is in the correct forwarding state after each transition.
Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is just a rename of physical ports from "lport" to "pport".  Not a
functional change.  OF-DPA uses logical ports (lport) for tunnels, but the
driver (and device) were using "lport" for physical ports.  Renaming physical
ports references to "pport", freeing up "lport" for use later with tunnels.
Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The rocker device returns error codes if something goes wrong with descriptor
processing.  Originally the device used standard errno codes for different
errors, but since those errno codes aren't portable across ARCHs, the device
now returns hard-coded error codes that stay constant across diff ARCHs.  Fix
driver to use those same hard-coded values.
Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add support for retrieving port level statistics from device.
Hook is added for ethtool's stats functionality. For example,

$ ethtool -S eth3
NIC statistics:
     rx_packets: 12
     rx_bytes: 2790
     rx_dropped: 0
     rx_errors: 0
     tx_packets: 8
     tx_bytes: 728
     tx_dropped: 0
     tx_errors: 0
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Acked-by: NScott Feldman <sfeldma@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch sets the NETIF_F_HW_SWITCH_OFFLOAD feature flag on rocker ports
Signed-off-by: NRoopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

bridge flags are needed inside ndo_bridge_setlink/dellink handlers to
avoid another call to parse IFLA_AF_SPEC inside these handlers

This is used later in this series
Signed-off-by: NRoopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add packet and byte counters for RX and TX paths.

$ ifconfig eth1
eth1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet6 fe80::5054:ff:fe12:3501  prefixlen 64  scopeid 0x20<link>
        ether 52:54:00:12:35:01  txqueuelen 1000  (Ethernet)
        RX packets 63  bytes 15813 (15.4 KiB)
        RX errors 1  dropped 0  overruns 0  frame 0
        TX packets 79  bytes 17991 (17.5 KiB)
        TX errors 7  dropped 0 overruns 0  carrier 0  collisions 0

Rx / Tx errors tested by injecting faults in qemu's hardware model for Rocker.

v2:
- moved counter locations to avoid potential use after free per Florian's comment
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Cc: Scott Feldman <sfeldma@gmail.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Contrary to common expectations for an "int" return, these functions
return only a positive value -- if used correctly they cannot even
return 0 because the message header will necessarily be in the skb.

This makes the very common pattern of

  if (genlmsg_end(...) < 0) { ... }

be a whole bunch of dead code. Many places also simply do

  return nlmsg_end(...);

and the caller is expected to deal with it.

This also commonly (at least for me) causes errors, because it is very
common to write

  if (my_function(...))
    /* error condition */

and if my_function() does "return nlmsg_end()" this is of course wrong.

Additionally, there's not a single place in the kernel that actually
needs the message length returned, and if anyone needs it later then
it'll be very easy to just use skb->len there.

Remove this, and make the functions void. This removes a bunch of dead
code as described above. The patch adds lines because I did

-	return nlmsg_end(...);
+	nlmsg_end(...);
+	return 0;

I could have preserved all the function's return values by returning
skb->len, but instead I've audited all the places calling the affected
functions and found that none cared. A few places actually compared
the return value with <= 0 in dump functionality, but that could just
be changed to < 0 with no change in behaviour, so I opted for the more
efficient version.

One instance of the error I've made numerous times now is also present
in net/phonet/pn_netlink.c in the route_dumpit() function - it didn't
check for <0 or <=0 and thus broke out of the loop every single time.
I've preserved this since it will (I think) have caused the messages to
userspace to be formatted differently with just a single message for
every SKB returned to userspace. It's possible that this isn't needed
for the tools that actually use this, but I don't even know what they
are so couldn't test that changing this behaviour would be acceptable.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>