Commit Graph

117 Commits

Author SHA1 Message Date
Vivien Didelot 6debb68a2d net: dsa: refine netdev event notifier
Rework the netdev event handler, similar to what the Mellanox Spectrum
driver does, to easily welcome more events later (for example
NETDEV_PRECHANGEUPPER) and use netdev helpers (such as
netif_is_bridge_master).

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-14 16:05:32 -04:00
Vivien Didelot 16bfa7024e net: dsa: make port_bridge_leave return void
netdev_upper_dev_unlink() which notifies NETDEV_CHANGEUPPER, returns
void, as well as del_nbp(). So there's no advantage to catch an eventual
error from the port_bridge_leave routine at the DSA level.

Make this routine void for the DSA layer and its existing drivers.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-14 16:05:31 -04:00
Vivien Didelot 71327a4e7d net: dsa: rename port_*_bridge routines
Rename DSA port_join_bridge and port_leave_bridge routines to
respectively port_bridge_join and port_bridge_leave in order to respect
an implicit Port::Bridge namespace.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-14 16:05:31 -04:00
Andrew Lunn b71be352f7 dsa: slave: Don't reference NULL pointer during phy_disconnect
When the phy is disconnected, the parent pointer to the netdev it was
attached to is set to NULL. The code then tries to suspend the phy,
but dsa_slave_fixed_link_update needs the parent pointer to determine
which switch the phy is connected to. So it dereferenced a NULL
pointer. Check for this condition.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-14 15:43:10 -04:00
Vivien Didelot fb2dabad69 net: dsa: support VLAN filtering switchdev attr
When a user explicitly requests VLAN filtering with something like:

    # echo 1 > /sys/class/net/<bridge>/bridge/vlan_filtering

Switchdev propagates a SWITCHDEV_ATTR_ID_BRIDGE_VLAN_FILTERING port
attribute.

Add support for it in the DSA layer with a new port_vlan_filtering
function to let drivers toggle 802.1Q filtering on user demand.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-01 16:24:51 -05:00
Vivien Didelot 477b184526 net: dsa: drop vlan_getnext
The VLAN GetNext operation is specific to some switches, and thus can be
complicated to implement for some drivers.

Remove the support for the vlan_getnext/port_pvid_get approach in favor
of the generic and simpler port_vlan_dump function.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-25 15:20:21 -05:00
Vivien Didelot 65aebfc002 net: dsa: add port_vlan_dump routine
Similar to port_fdb_dump, add a port_vlan_dump function to DSA drivers
which gets passed the switchdev VLAN object and callback.

This function, if implemented, takes precedence over the soon legacy
vlan_getnext/port_pvid_get approach.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-25 15:20:20 -05:00
Vivien Didelot 9d2dd73669 net: dsa: remove dsa_bridge_check_vlan_range
DSA drivers may support multiple bridge groups with the same hardware
VLAN. The mv88e6xxx driver which cannot yet, already has its own check
for overlapping bridges. Thus remove the check from the DSA layer.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-23 14:52:46 -05:00
Vivien Didelot a6692754d6 net: dsa: pass bridge down to drivers
Some DSA drivers may or may not support multiple software bridges on top
of an hardware switch.

It is more convenient for them to access the bridge's net_device for
finer configuration.

Removing the need to craft and access a bitmask also simplifies the
code.

This patch changes the signature of bridge related functions, update DSA
drivers, and removes dsa_slave_br_port_mask.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-23 14:52:46 -05:00
Florian Fainelli 73dcb55653 net: dsa: Unregister slave_dev in error path
With commit 0071f56e46 ("dsa: Register netdev before phy"), we are now trying
to free a network device that has been previously registered, and in case of
errors, this will make us hit the BUG_ON(dev->reg_state != NETREG_UNREGISTERED)
condition.

Fix this by adding a missing unregister_netdev() before free_netdev().

Fixes: 0071f56e46 ("dsa: Register netdev before phy")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-17 22:05:16 -05:00
Sascha Hauer a407054f83 net: dsa: remove phy_disconnect from error path
The phy has not been initialized, disconnecting it in the error
path results in a NULL pointer exception. Drop the phy_disconnect
from the error path.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-16 16:04:08 -05:00
Andrew Lunn 0071f56e46 dsa: Register netdev before phy
When the phy is connected, an info message is printed. If the netdev
it is attached to has not been registered yet, the name
'uninitialised' in the output. By registering the netdev first, then
connecting they phy, we can avoid this.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-07 14:31:26 -05:00
Andrew Lunn 7f854420fb phy: Add API for {un}registering an mdio device to a bus.
Rather than have drivers directly manipulate the mii_bus structure,
provide and API for registering and unregistering devices on an MDIO
bus, and performing lookups.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-07 14:31:26 -05:00
Andrew Lunn 2220943a21 phy: Centralise print about attached phy
Many Ethernet drivers contain the same netdev_info() print statement
about the attached phy. Move it into the phy device code. Additionally
add a varargs function which can be used to append additional
information.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-07 14:31:25 -05:00
Neil Armstrong cda5c15b23 net: dsa: move dsa slave destroy code to slave.c
Move dsa slave dedicated code from dsa_switch_destroy to a new
dsa_slave_destroy function in slave.c.
Add the netif_carrier_off and phy_disconnect calls in order to
correctly cleanup the netdev state and PHY state machine.

Signed-off-by: Frode Isaksen <fisaksen@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-07 16:35:50 -05:00
Vivien Didelot 76e398a627 net: dsa: use switchdev obj for VLAN add/del ops
Simplify DSA by pushing the switchdev objects for VLAN add and delete
operations down to its drivers. Currently only mv88e6xxx is affected.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-01 15:56:11 -05:00
Vivien Didelot 1a49a2fbf8 net: dsa: remove port_fdb_getnext
No driver implements port_fdb_getnext anymore, and port_fdb_dump is
preferred anyway, so remove this function from DSA.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-22 07:38:45 -07:00
Vivien Didelot ea70ba9806 net: dsa: add port_fdb_dump function
Not all switch chips support a Get Next operation to iterate on its FDB.
So add a more simple port_fdb_dump function for them.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-22 07:38:35 -07:00
Jiri Pirko 850d0cbc91 switchdev: remove pointers from switchdev objects
When object is used in deferred work, we cannot use pointers in
switchdev object structures because the memory they point at may be already
used by someone else. So rather do local copy of the value.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Scott Feldman <sfeldma@gmail.com>
Reviewed-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-15 06:09:49 -07:00
Jiri Pirko f7fadf3047 switchdev: make struct switchdev_attr parameter const for attr_set calls
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-15 06:09:46 -07:00
Vivien Didelot efd29b3d82 net: dsa: do not warn unsupported bridge ops
A DSA driver may not provide the port_join_bridge and port_leave_bridge
functions, so don't warn in such case.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-13 04:26:30 -07:00
Vivien Didelot 8057b3e7a1 net: dsa: use switchdev obj in port_fdb_del
For consistency with the FDB add operation, propagate the
switchdev_obj_port_fdb structure in the DSA drivers.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-11 05:28:52 -07:00
Vivien Didelot 1f36faf269 net: dsa: push prepare phase in port_fdb_add
Now that the prepare phase is pushed down to the DSA drivers, propagate
it to the port_fdb_add function.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-11 05:28:50 -07:00
Vivien Didelot 146a32067b net: dsa: add port_fdb_prepare
Push the prepare phase for FDB operations down to the DSA drivers, with
a new port_fdb_prepare function. Currently only mv88e6xxx is affected.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-11 05:28:49 -07:00
Russell King d25b8e7429 net: dsa: better error reporting
Add additional error reporting to the generic DSA code, so it's easier
to debug when things go wrong.  This was useful when initially bringing
up 88e6176 on a new board.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-07 02:58:49 -07:00
Jiri Pirko 9e8f4a548a switchdev: push object ID back to object structure
Suggested-by: Scott Feldman <sfeldma@gmail.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Scott Feldman <sfeldma@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-03 04:49:40 -07:00
Jiri Pirko 648b4a995a switchdev: bring back switchdev_obj and use it as a generic object param
Replace "void *obj" with a generic structure. Introduce couple of
helpers along that.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Scott Feldman <sfeldma@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-03 04:49:39 -07:00
Jiri Pirko 52ba57cfdc switchdev: rename switchdev_obj_fdb to switchdev_obj_port_fdb
Make the struct name in sync with object id name.

Suggested-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Scott Feldman <sfeldma@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-03 04:49:39 -07:00
Jiri Pirko 8f24f3095d switchdev: rename switchdev_obj_vlan to switchdev_obj_port_vlan
Make the struct name in sync with object id name.

Suggested-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Scott Feldman <sfeldma@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-03 04:49:38 -07:00
Jiri Pirko 1f86839874 switchdev: rename SWITCHDEV_ATTR_* enum values to SWITCHDEV_ATTR_ID_*
To be aligned with obj.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Scott Feldman <sfeldma@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-03 04:49:37 -07:00
Jiri Pirko 57d80838da switchdev: rename SWITCHDEV_OBJ_* enum values to SWITCHDEV_OBJ_ID_*
Suggested-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Scott Feldman <sfeldma@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-03 04:49:36 -07:00
Vivien Didelot b8d866ac6a net: dsa: fix preparation of a port STP update
Because of the default 0 value of ret in dsa_slave_port_attr_set, a
driver may return -EOPNOTSUPP from the commit phase of a STP state,
which triggers a WARN() from switchdev.

This happened on a 6185 switch which does not support hardware bridging.

Reported-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Acked-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-29 21:35:06 -07:00
Vivien Didelot ab06900230 net: switchdev: abstract object in add/del ops
Similar to the notifier_call callback of a notifier_block, change the
function signature of switchdev add and del operations to:

    int switchdev_port_obj_add/del(struct net_device *dev,
                                   enum switchdev_obj_id id, void *obj);

This allows the caller to pass a specific switchdev_obj_* structure
instead of the generic switchdev_obj one.

Drivers implementation of these operations and switchdev have been
changed accordingly.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-29 21:31:59 -07:00
Vivien Didelot 25f07adc47 net: switchdev: pass callback to dump operation
Similar to the notifier_call callback of a notifier_block, change the
function signature of switchdev dump operation to:

    int switchdev_port_obj_dump(struct net_device *dev,
                                enum switchdev_obj_id id, void *obj,
                                int (*cb)(void *obj));

This allows the caller to pass and expect back a specific
switchdev_obj_* structure instead of the generic switchdev_obj one.

Drivers implementation of dump operation can now expect this specific
structure and call the callback with it. Drivers have been changed
accordingly.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-29 21:31:59 -07:00
Vivien Didelot 03d5fb1862 net: switchdev: remove dev from switchdev_obj cb
The net_device associated to a dump operation does not have to be passed
to the callback. switchdev stores it in a superset struct, if needed.

Also some drivers (such as DSA drivers) may not have easy access to it.

This will simplify pushing the callback function down to the drivers.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-29 21:31:59 -07:00
Florian Fainelli f37db85d0c net: dsa: Set a "dsa" device_type
Provide a device_type information for slave network devices created by
DSA, this is useful for user-space application to easily locate/search
for devices of a specific kind.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-25 12:25:16 -07:00
Jiri Pirko 79a62eb22a dsa: use prepare/commit switchdev transaction helpers
The enum is going to disappear, use the helpers instead.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-24 22:59:22 -07:00
Jiri Pirko f8db83486e switchdev: move transaction phase enum under transaction structure
Before it disappears completely, move transaction phase enum under
transaction structure and make attr/obj structures a bit cleaner.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-24 22:59:21 -07:00
Jiri Pirko 7ea6eb3f56 switchdev: introduce transaction item queue for attr_set and obj_add
Now, the memory allocation in prepare/commit state is done separatelly
in each driver (rocker). Introduce the similar mechanism in generic
switchdev code, in form of queue. That can be used not only for memory
allocations, but also for different items. Abort item destruction
is handled as well.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-24 22:59:21 -07:00
Jiri Pirko 69f5df491e switchdev: rename "trans" to "trans_ph".
This is temporary, name "trans" will be used for something else and
"trans_ph" will eventually disappear.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-24 22:59:21 -07:00
Phil Sutter 0a5f107b67 net: dsa: convert to using IFF_NO_QUEUE
Signed-off-by: Phil Sutter <phil@nwl.cc>
Cc: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-18 11:55:06 -07:00
Vivien Didelot 1114953615 net: dsa: add support for switchdev VLAN objects
Add new functions in DSA drivers to access hardware VLAN entries through
SWITCHDEV_OBJ_PORT_VLAN objects:

 - port_pvid_get() and vlan_getnext() to dump a VLAN
 - port_vlan_del() to exclude a port from a VLAN
 - port_pvid_set() and port_vlan_add() to join a port to a VLAN

The DSA infrastructure will ensure that each VLAN of the given range
does not already belong to another bridge. If it does, it will fallback
to software VLAN and won't program the hardware.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-13 21:31:12 -07:00
David S. Miller 182ad468e7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/cavium/Kconfig

The cavium conflict was overlapping dependency
changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-13 16:23:11 -07:00
Florian Fainelli 211c504a44 net: dsa: Do not override PHY interface if already configured
In case we need to divert reads/writes using the slave MII bus, we may have
already fetched a valid PHY interface property from Device Tree, and that
mode is used by the PHY driver to make configuration decisions.

If we could not fetch the "phy-mode" property, we will assign p->phy_interface
to PHY_INTERFACE_MODE_NA, such that we can actually check for that condition as
to whether or not we should override the interface value.

Fixes: 19334920ea ("net: dsa: Set valid phy interface type")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-12 14:29:50 -07:00
Vivien Didelot ba14d9eb19 net: dsa: add support for switchdev FDB objects
Implement the switchdev_port_obj_{add,del,dump} functions in DSA to
support the SWITCHDEV_OBJ_PORT_FDB objects.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-11 12:03:19 -07:00
Vivien Didelot 2a778e1b58 net: dsa: change FDB routines prototypes
Change the prototype of port_getnext to include a vid parameter.

This is necessary to introduce the support for VLAN.

Also rename the fdb_{add,del,getnext} function pointers to
port_fdb_{add,del,getnext} since they are specific to a given port.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-11 12:03:19 -07:00
David S. Miller cdf0969763 Revert "Merge branch 'mv88e6xxx-switchdev-fdb'"
This reverts commit f1d5ca4344, reversing
changes made to 4933d85c51.

I applied v2 instead of v3.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-11 12:00:37 -07:00
Vivien Didelot 55045ddded net: dsa: add support for switchdev FDB objects
Remove the fdb_{add,del,getnext} function pointer in favor of new
port_fdb_{add,del,getnext}.

Implement the switchdev_port_obj_{add,del,dump} functions in DSA to
support the SWITCHDEV_OBJ_PORT_FDB objects.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-09 22:48:09 -07:00
Florian Fainelli 04ff53f96a net: dsa: Add netconsole support
Add support for using DSA slave network devices with netconsole, which
requires us to allocate and free custom netpoll instances and invoke the
parent network device poll controller callback.

In order for netconsole to work, we need to construct the DSA tag, but
not queue the skb for transmission on the master network device xmit
function.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-31 15:45:37 -07:00
Florian Fainelli 4ed70ce9f0 net: dsa: Refactor transmit path to eliminate duplication
All tagging protocols do the same thing: increment device statistics,
make room for the tag to be inserted, create the tag, invoke the parent
network device transmit function.

In order to prepare for adding netpoll support, which requires the tag
creation, but not using the parent network device transmit function, do
some little refactoring which eliminates duplication between the 4
tagging protocols supported.

We need to return a sk_buff pointer back to the caller because the tag
specific transmit function may have to reallocate the original skb (e.g:
tag_trailer.c) and this is the one we should be transmitting, not the
original sk_buff we were passed.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-31 15:45:37 -07:00