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2022-11-22net: dsa: move tagging protocol code to tag.{c,h}Vladimir Oltean1-1/+1
It would be nice if tagging protocol drivers could include just the header they need, since they are (mostly) data path and isolated from most of the other DSA core code does. Create a tag.c and a tag.h file which are meant to support tagging protocol drivers. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-17net: dsa: provide a second modalias to tag proto drivers based on their nameVladimir Oltean1-2/+4
Currently, tagging protocol drivers have a modalias of "dsa_tag:id-<number>", where the number is one of DSA_TAG_PROTO_*_VALUE. This modalias makes it possible for the request_module() call in dsa_tag_driver_get() to work, given the input it has - an integer returned by ds->ops->get_tag_protocol(). It is also possible to change tagging protocols at (pseudo-)runtime, via sysfs or via device tree, and this works via the name string of the tagging protocol rather than via its id (DSA_TAG_PROTO_*_VALUE). In the latter case, there is no request_module() call, because there is no association that the DSA core has between the string name and the ID, to construct the modalias. The module is simply assumed to have been inserted. This is actually slightly problematic when the tagging protocol change should take place at probe time, since it's expected that the dependency module should get autoloaded. For this purpose, let's introduce a second modalias, so that the DSA core can call request_module() by name. There is no reason to make the modalias by name optional, so just modify the MODULE_ALIAS_DSA_TAG_DRIVER() macro to take both the ID and the name as arguments, and generate two modaliases behind the scenes. Suggested-by: Michael Walle <michael@walle.cc> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Tested-by: Michael Walle <michael@walle.cc> # on kontron-sl28 w/ ocelot_8021q Tested-by: Michael Walle <michael@walle.cc> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-02net: dsa: tag_qca: add support for handling mgmt and MIB Ethernet packetAnsuel Smith1-3/+36
Add connect/disconnect helper to assign private struct to the DSA switch. Add support for Ethernet mgmt and MIB if the DSA driver provide an handler to correctly parse and elaborate the data. Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-02net: dsa: tag_qca: add define for handling MIB packetAnsuel Smith1-0/+4
Add struct to correctly parse a mib Ethernet packet. Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-02net: dsa: tag_qca: add define for handling mgmt Ethernet packetAnsuel Smith1-3/+12
Add all the required define to prepare support for mgmt read/write in Ethernet packet. Any packet of this type has to be dropped as the only use of these special packet is receive ack for an mgmt write request or receive data for an mgmt read request. A struct is used that emulates the Ethernet header but is used for a different purpose. Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-02net: dsa: tag_qca: enable promisc_on_master flagAnsuel Smith1-0/+1
Ethernet MDIO packets are non-standard and DSA master expects the first 6 octets to be the MAC DA. To address these kind of packet, enable promisc_on_master flag for the tagger. Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-02net: dsa: tag_qca: move define to include linux/dsaAnsuel Smith1-15/+1
Move tag_qca define to include dir linux/dsa as the qca8k require access to the tagger define to support in-band mdio read/write using ethernet packet. Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-02net: dsa: tag_qca: convert to FIELD macroAnsuel Smith1-19/+15
Convert driver to FIELD macro to drop redundant define. Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-11net: dsa: create a helper for locating EtherType DSA headers on TXVladimir Oltean1-1/+1
Create a similar helper for locating the offset to the DSA header relative to skb->data, and make the existing EtherType header taggers to use it. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-11net: dsa: create a helper for locating EtherType DSA headers on RXVladimir Oltean1-5/+1
It seems that protocol tagging driver writers are always surprised about the formula they use to reach their EtherType header on RX, which becomes apparent from the fact that there are comments in multiple drivers that mention the same information. Create a helper that returns a void pointer to skb->data - 2, as well as centralize the explanation why that is the case. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-11net: dsa: create a helper which allocates space for EtherType DSA headersVladimir Oltean1-1/+1
Hide away the memmove used by DSA EtherType header taggers to shift the MAC SA and DA to the left to make room for the header, after they've called skb_push(). The call to skb_push() is still left explicit in drivers, to be symmetric with dsa_strip_etype_header, and because not all callers can be refactored to do it (for example, brcm_tag_xmit_ll has common code for a pre-Ethernet DSA tag and an EtherType DSA tag). Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-11net: dsa: create a helper that strips EtherType DSA headers on RXVladimir Oltean1-2/+1
All header taggers open-code a memmove that is fairly not all that obvious, and we can hide the details behind a helper function, since the only thing specific to the driver is the length of the header tag. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-02net: dsa: remove the struct packet_type argument from dsa_device_ops::rcv()Vladimir Oltean1-2/+1
No tagging driver uses this. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-11net: dsa: generalize overhead for taggers that use both headers and trailersVladimir Oltean1-1/+1
Some really really weird switches just couldn't decide whether to use a normal or a tail tagger, so they just did both. This creates problems for DSA, because we only have the concept of an 'overhead' which can be applied to the headroom or to the tailroom of the skb (like for example during the central TX reallocation procedure), depending on the value of bool tail_tag, but not to both. We need to generalize DSA to cater for these odd switches by transforming the 'overhead / tail_tag' pair into 'needed_headroom / needed_tailroom'. The DSA master's MTU is increased to account for both. The flow dissector code is modified such that it only calls the DSA adjustment callback if the tagger has a non-zero header length. Taggers are trivially modified to declare either needed_headroom or needed_tailroom, based on the tail_tag value that they currently declare. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-11-02net: dsa: tag_qca: let DSA core deal with TX reallocationVladimir Oltean1-3/+0
Now that we have a central TX reallocation procedure that accounts for the tagger's needed headroom in a generic way, we can remove the skb_cow_head call. Cc: John Crispin <john@phrozen.org> Cc: Alexander Lobakin <alobakin@pm.me> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-09-26net: dsa: tag_qca: use the generic flow dissector procedureVladimir Oltean1-8/+0
Remove the .flow_dissect procedure, so the flow dissector will call the generic variant which works for this tagging protocol. Cc: John Crispin <john@phrozen.org> Cc: Alexander Lobakin <alobakin@pm.me> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-26net: dsa: make the .flow_dissect tagger callback return voidVladimir Oltean1-4/+2
There is no tagger that returns anything other than zero, so just change the return type appropriately. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-05net: dsa: tag_qca.c: Fix warning for __be16 vs u16Andrew Lunn1-3/+5
net/dsa/tag_qca.c:48:15: warning: incorrect type in assignment (different base types) net/dsa/tag_qca.c:48:15: expected unsigned short [usertype] net/dsa/tag_qca.c:48:15: got restricted __be16 [usertype] net/dsa/tag_qca.c:68:13: warning: incorrect type in assignment (different base types) net/dsa/tag_qca.c:68:13: expected restricted __be16 [usertype] hdr net/dsa/tag_qca.c:68:13: got int net/dsa/tag_qca.c:71:16: warning: restricted __be16 degrades to integer net/dsa/tag_qca.c:81:17: warning: restricted __be16 degrades to integer 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>
2020-02-14net: dsa: tag_qca: Make sure there is headroom for tagPer Forlin1-1/+1
Passing tag size to skb_cow_head will make sure there is enough headroom for the tag data. This change does not introduce any overhead in case there is already available headroom for tag. Signed-off-by: Per Forlin <perfn@axis.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-16net: dsa: tag_qca: fix doubled Tx statisticsAlexander Lobakin1-3/+0
DSA subsystem takes care of netdev statistics since commit 4ed70ce9f01c ("net: dsa: Refactor transmit path to eliminate duplication"), so any accounting inside tagger callbacks is redundant and can lead to messing up the stats. This bug is present in Qualcomm tagger since day 0. Fixes: cafdc45c949b ("net-next: dsa: add Qualcomm tag RX/TX handler") Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Alexander Lobakin <alobakin@dlink.ru> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-28dsa: Cleanup unneeded table and make tag structures staticAndrew Lunn1-1/+1
Now that tag drivers dynamically register, we don't need the static table. Remove it. This also means the tag driver structures can be made static. 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>
2019-04-28dsa: Add boilerplate helper to register DSA tag driver modulesAndrew Lunn1-0/+2
A DSA tag driver module will need to register the tag protocols it implements with the DSA core. Add macros containing this boiler plate. The registration/unregistration code is currently just a stub. A Later patch will add the real implementation. Signed-off-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> v2 Fix indent of #endif Rewrite to move list pointer into a new structure v3 Move kdoc next to macro Fix THIS_MODULE indentation Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-28dsa: Add TAG protocol to tag opsAndrew Lunn1-0/+1
In order that we can match the tagging protocol a switch driver request to the tagger, we need to know what protocol the tagger supports. Add this information to the ops structure. Signed-off-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> v2 More tag protocol to end of structure to keep hot members at the beginning. Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-28dsa: Add MODULE_LICENSE to tag driversAndrew Lunn1-0/+1
All the tag drivers are some variant of GPL. Add a MODULE_LICENSE() indicating this, so the drivers can later be compiled as modules. 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>
2019-04-28dsa: Add MODULE_ALIAS to taggers in preparation to become modulesAndrew Lunn1-0/+2
When the tag drivers become modules, we will need to dynamically load them based on what the switch drivers need. Add aliases to map between the TAG protocol and the driver. In order to do this, we need the tag protocol number as something which the C pre-processor can stringinfy. Only the compiler knows the value of an enum, CPP cannot use them. So add #defines. 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>
2019-04-28dsa: Move tagger name into its ops structureAndrew Lunn1-0/+1
Rather than keep a list to map a tagger ops to a name, place the name into the ops structure. This removes the hard coded list, a step towards making the taggers more dynamic. Signed-off-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> v2: Move name to end of structure, keeping the hot entries at the beginning. Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-28dsa: Add SPDX header to tag drivers.Andrew Lunn1-9/+1
Add an SPDX header, and remove the license boilerplate text. 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>
2019-03-28net: dsa: Implement flow_dissect callback for tag_qcaxiaofeis1-0/+10
Add flow_dissect for qca tagged packet to get the right hash. Signed-off-by: Xiaofei Shen <xiaofeis@codeaurora.org> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Vinod Koul <vkoul@kernel.org> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-06net: dsa: Add overhead to tag protocol ops.Andrew Lunn1-0/+1
Each DSA tag protocol needs to add additional headers to the Ethernet frame in order to direct it towards a specific switch egress port. It must also remove the head from a frame received from a switch. Indicate the maximum size of these headers in the tag protocol ops structure, so the core can take these overheads into account. Signed-off-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-18net: dsa: rename dsa_master_get_slaveVivien Didelot1-1/+1
The dsa_master_get_slave is slightly confusing since the idiomatic "get" term often suggests reference counting, in symmetry to "put". Rename it to dsa_master_find_slave to make the look up operation clear. Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-18net: dsa: add slave to port helperVivien Didelot1-3/+2
Many portions of DSA core code require to get the dsa_port structure corresponding to a slave net_device. For this purpose, introduce a dsa_slave_to_port() helper. Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-01net: dsa: add master helper to look up slavesVivien Didelot1-14/+3
The DSA tagging code does not need to know about the DSA architecture, it only needs to return the slave device corresponding to the source port index (and eventually the source device index for cascade-capable switches) parsed from the frame received on the master device. For this purpose, provide an inline dsa_master_get_slave helper which validates the device and port indexes and look up the slave device. This makes the tagging rcv functions more concise and robust, and also makes dsa_get_cpu_port obsolete. Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-21dsa: remove unused net_device arg from handlersFlorian Westphal1-2/+1
compile tested only, but saw no warnings/errors with allmodconfig build. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-13net: dsa: Introduce dsa_get_cpu_port()Florian Fainelli1-1/+2
Introduce a helper function which will return a reference to the CPU port used in a dsa_switch_tree. Right now this is a singleton, but this will change once we introduce multi-CPU port support, so ease the transition by converting the affected code paths. Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-01net: dsa: factor skb freeing on xmitVivien Didelot1-5/+1
As of a86d8becc3f0 ("net: dsa: Factor bottom tag receive functions"), the rcv caller frees the original SKB in case or error. Be symmetric with that and make the xmit caller do the same. At the same time, fix the checkpatch NULL comparison check: CHECK: Comparison to NULL could be written "!nskb" #208: FILE: net/dsa/tag_trailer.c:35: + if (nskb == NULL) Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-01net: dsa: remove out_drop label in taggers rcvVivien Didelot1-7/+4
Many rcv functions from net/dsa/tag_*.c have a useless out_drop goto label which simply returns NULL. Kill it in favor of the obvious. Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-18net: dsa: include dsa.h only onceVivien Didelot1-1/+1
The public include/net/dsa.h file is meant for DSA drivers, while all DSA core files share a common private header net/dsa/dsa_priv.h file. Ensure that dsa_priv.h is the only DSA core file to include net/dsa.h, and add a new line to separate absolute and relative headers at the same time. Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-17net: dsa: store CPU port pointer in the treeVivien Didelot1-1/+1
A dsa_switch_tree instance holds a dsa_switch pointer and a port index to identify the switch port to which the CPU is attached. Now that the DSA layer has a dsa_port structure to hold this data, use it to point the switch CPU port. This patch simply substitutes s/dst->cpu_switch/dst->cpu_dp->ds/ and s/dst->cpu_port/dst->cpu_dp->index/. Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-08net: dsa: Factor bottom tag receive functionsFlorian Fainelli1-13/+5
All DSA tag receive functions do strictly the same thing after they have located the originating source port from their tag specific protocol: - push ETH_HLEN bytes - set pkt_type to PACKET_HOST - call eth_type_trans() - bump up counters - call netif_receive_skb() Factor all of that into dsa_switch_rcv(). This also makes us return a pointer to a sk_buff, which makes us symetric with the xmit function. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-08net: dsa: Move skb_unshare() to dsa_switch_rcv()Florian Fainelli1-5/+0
All DSA tag receive functions need to unshare the skb before mangling it, move this to the generic dsa_switch_rcv() function which will allow us to make the tag receive function return their mangled skb without caring about freeing a NULL skb. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-08net: dsa: Do not check for NULL dst in tag parsersFlorian Fainelli1-3/+0
dsa_switch_rcv() already tests for dst == NULL, so there is no need to duplicate the same check within the tag receive functions. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-28net: break include loop netdevice.h, dsa.h, devlink.hAndrew Lunn1-0/+1
There is an include loop between netdevice.h, dsa.h, devlink.h because of NETDEV_ALIGN, making it impossible to use devlink structures in dsa.h. Break this loop by taking dsa.h out of netdevice.h, add a forward declaration of dsa_switch_tree and netdev_set_default_ethtool_ops() function, which is what netdevice.h requires. No longer having dsa.h in netdevice.h means the includes in dsa.h no longer get included. This breaks a few other files which depend on these includes. Add these directly in the affected file. 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>
2017-01-29net: dsa: store a dsa_port in dsa_slave_privVivien Didelot1-1/+1
Store a pointer to the dsa_port structure in the dsa_slave_priv structure, instead of the switch/port index. This will allow to store more information such as the bridge device, needed in DSA drivers for multi-chip configuration. Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-18net: dsa: use cpu_switch instead of ds[0]Vivien Didelot1-1/+1
Now that the DSA Ethernet switches are true Linux devices, the CPU switch is not necessarily the first one. If its address is higher than the second switch on the same MDIO bus, its index will be 1, not 0. Avoid any confusion by using dst->cpu_switch instead of dst->ds[0]. Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-16net-next: dsa: add Qualcomm tag RX/TX handlerJohn Crispin1-0/+138
Add support for the 2-bytes Qualcomm tag that gigabit switches such as the QCA8337/N might insert when receiving packets, or that we need to insert while targeting specific switch ports. The tag is inserted directly behind the ethernet header. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: John Crispin <john@phrozen.org> Signed-off-by: David S. Miller <davem@davemloft.net>