Commit Graph

693 Commits

Author SHA1 Message Date
David S. Miller
13dfb3fa49 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Just minor overlapping changes in the conflicts here.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-06 18:44:57 -07:00
Vladimir Oltean
93fa8587b2 net: dsa: sja1105: Fix memory leak on meta state machine error path
When RX timestamping is enabled and two link-local (non-meta) frames are
received in a row, this constitutes an error.

The tagger is always caching the last link-local frame, in an attempt to
merge it with the meta follow-up frame when that arrives. To recover
from the above error condition, the initial cached link-local frame is
dropped and the second frame in a row is cached (in expectance of the
second meta frame).

However, when dropping the initial link-local frame, its backing memory
was being leaked.

Fixes: f3097be21b ("net: dsa: sja1105: Add a state machine for RX timestamping")
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-06 14:37:02 -07:00
Vladimir Oltean
f163fed276 net: dsa: sja1105: Fix memory leak on meta state machine normal path
After a meta frame is received, it is associated with the cached
sp->data->stampable_skb from the DSA tagger private structure.

Cached means its refcount is incremented with skb_get() in order for
dsa_switch_rcv() to not free it when the tagger .rcv returns NULL.

The mistake is that skb_unref() is not the correct function to use. It
will correctly decrement the refcount (which will go back to zero) but
the skb memory will not be freed.  That is the job of kfree_skb(), which
also calls skb_unref().

But it turns out that freeing the cached stampable_skb is in fact not
necessary.  It is still a perfectly valid skb, and now it is even
annotated with the partial RX timestamp.  So remove the skb_copy()
altogether and simply pass the stampable_skb with a refcount of 1
(incremented by us, decremented by dsa_switch_rcv) up the stack.

Fixes: f3097be21b ("net: dsa: sja1105: Add a state machine for RX timestamping")
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-06 14:37:02 -07:00
Vivien Didelot
48e2331197 net: dsa: dump CPU port regs through master
Merge the CPU port registers dump into the master interface registers
dump through ethtool, by nesting the ethtool_drvinfo and ethtool_regs
structures of the CPU port into the dump.

drvinfo->regdump_len will contain the full data length, while regs->len
will contain only the master interface registers dump length.

This allows for example to dump the CPU port registers on a ZII Dev
C board like this:

    # ethtool -d eth1
    0x004:                                              0x00000000
    0x008:                                              0x0a8000aa
    0x010:                                              0x01000000
    0x014:                                              0x00000000
    0x024:                                              0xf0000102
    0x040:                                              0x6d82c800
    0x044:                                              0x00000020
    0x064:                                              0x40000000
    0x084: RCR (Receive Control Register)               0x47c00104
        MAX_FL (Maximum frame length)                   1984
        FCE (Flow control enable)                       0
        BC_REJ (Broadcast frame reject)                 0
        PROM (Promiscuous mode)                         0
        DRT (Disable receive on transmit)               0
        LOOP (Internal loopback)                        0
    0x0c4: TCR (Transmit Control Register)              0x00000004
        RFC_PAUSE (Receive frame control pause)         0
        TFC_PAUSE (Transmit frame control pause)        0
        FDEN (Full duplex enable)                       1
        HBC (Heartbeat control)                         0
        GTS (Graceful transmit stop)                    0
    0x0e4:                                              0x76735d6d
    0x0e8:                                              0x7e9e8808
    0x0ec:                                              0x00010000
    .
    .
    .
    88E6352  Switch Port Registers
    ------------------------------
    00: Port Status                            0x4d04
          Pause Enabled                        0
          My Pause                             1
          802.3 PHY Detected                   0
          Link Status                          Up
          Duplex                               Full
          Speed                                100 or 200 Mbps
          EEE Enabled                          0
          Transmitter Paused                   0
          Flow Control                         0
          Config Mode                          0x4
    01: Physical Control                       0x003d
          RGMII Receive Timing Control         Default
          RGMII Transmit Timing Control        Default
          200 BASE Mode                        100
          Flow Control's Forced value          0
          Force Flow Control                   0
          Link's Forced value                  Up
          Force Link                           1
          Duplex's Forced value                Full
          Force Duplex                         1
          Force Speed                          100 or 200 Mbps
    .
    .
    .

Signed-off-by: Vivien Didelot <vivien.didelot@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-06 14:08:32 -07:00
Marek Vasut
267df70fe8 net: dsa: ksz: Drop NET_DSA_TAG_KSZ9477
This Kconfig option is unused, drop it.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: David S. Miller <davem@davemloft.net>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Tristram Ha <Tristram.Ha@microchip.com>
Cc: Vivien Didelot <vivien.didelot@gmail.com>
Cc: Woojung Huh <woojung.huh@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-06 11:59:17 -07:00
Tristram Ha
016e43a26b net: dsa: ksz: Add KSZ8795 tag code
Add DSA tag code for Microchip KSZ8795 switch. The switch is simpler
and the tag is only 1 byte, instead of 2 as is the case with KSZ9477.

Signed-off-by: Tristram Ha <Tristram.Ha@microchip.com>
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: David S. Miller <davem@davemloft.net>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Tristram Ha <Tristram.Ha@microchip.com>
Cc: Vivien Didelot <vivien.didelot@gmail.com>
Cc: Woojung Huh <woojung.huh@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-30 15:12:50 -07:00
Pablo Neira Ayuso
14bfb13f0e net: flow_offload: add flow_block structure and use it
This object stores the flow block callbacks that are attached to this
block. Update flow_block_cb_lookup() to take this new object.

This patch restores the block sharing feature.

Fixes: da3eeb904f ("net: flow_offload: add list handling functions")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-19 21:27:45 -07:00
Pablo Neira Ayuso
a732331151 net: flow_offload: rename tc_setup_cb_t to flow_setup_cb_t
Rename this type definition and adapt users.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-19 21:27:45 -07:00
Pablo Neira Ayuso
0c7294ddae net: flow_offload: remove netns parameter from flow_block_cb_alloc()
No need to annotate the netns on the flow block callback object,
flow_block_cb_is_busy() already checks for used blocks.

Fixes: d63db30c85 ("net: flow_offload: add flow_block_cb_alloc() and flow_block_cb_free()")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-19 21:27:45 -07:00
Wei Yongjun
008cfbaa3f net: dsa: sja1105: Fix missing unlock on error in sk_buff()
Add the missing unlock before return from function sk_buff()
in the error handling case.

Fixes: f3097be21b ("net: dsa: sja1105: Add a state machine for RX timestamping")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-18 16:32:39 -07:00
Vivien Didelot
08cc83cc7f net: dsa: add support for BRIDGE_MROUTER attribute
This patch adds support for enabling or disabling the flooding of
unknown multicast traffic on the CPU ports, depending on the value
of the switchdev SWITCHDEV_ATTR_ID_BRIDGE_MROUTER attribute.

The current behavior is kept unchanged but a user can now prevent
the CPU conduit to be flooded with a lot of unregistered traffic that
the network stack needs to filter in software with e.g.:

    echo 0 > /sys/class/net/br0/multicast_router

Signed-off-by: Vivien Didelot <vivien.didelot@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-09 14:49:34 -07:00
Pablo Neira Ayuso
0d4fd02e71 net: flow_offload: add flow_block_cb_is_busy() and use it
This patch adds a function to check if flow block callback is already in
use.  Call this new function from flow_block_cb_setup_simple() and from
drivers.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-09 14:38:50 -07:00
Pablo Neira Ayuso
955bcb6ea0 drivers: net: use flow block API
This patch updates flow_block_cb_setup_simple() to use the flow block API.
Several drivers are also adjusted to use it.

This patch introduces the per-driver list of flow blocks to account for
blocks that are already in use.

Remove tc_block_offload alias.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-09 14:38:50 -07:00
Pablo Neira Ayuso
32f8c4093a net: flow_offload: rename TCF_BLOCK_BINDER_TYPE_* to FLOW_BLOCK_BINDER_TYPE_*
Rename from TCF_BLOCK_BINDER_TYPE_* to FLOW_BLOCK_BINDER_TYPE_* and
remove temporary tcf_block_binder_type alias.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-09 14:38:50 -07:00
Pablo Neira Ayuso
9c0e189ec9 net: flow_offload: rename TC_BLOCK_{UN}BIND to FLOW_BLOCK_{UN}BIND
Rename from TC_BLOCK_{UN}BIND to FLOW_BLOCK_{UN}BIND and remove
temporary tc_block_command alias.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-09 14:38:50 -07:00
Vivien Didelot
79b139f4bc net: dsa: use switchdev handle helpers
Get rid of the dsa_slave_switchdev_port_{attr_set,obj}_event functions
in favor of the switchdev_handle_port_{attr_set,obj_add,obj_del}
helpers which recurse into the lower devices of the target interface.

This has the benefit of being aware of the operations made on the
bridge device itself, where orig_dev is the bridge, and dev is the
slave. This can be used later to configure the hardware switches.

Only VLAN and (port) MDB objects not directly targeting the slave
device are unsupported at the moment, so skip this case in their
respective case statements.

Signed-off-by: Vivien Didelot <vivien.didelot@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-14 20:20:07 -07:00
Vivien Didelot
f3b78049d4 net: dsa: make dsa_slave_dev_check use const
The switchdev handle helpers make use of a device checking helper
requiring a const net_device. Make dsa_slave_dev_check compliant
to this.

Signed-off-by: Vivien Didelot <vivien.didelot@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-14 20:20:07 -07:00
Vivien Didelot
14aafbd822 net: dsa: do not check orig_dev in vlan del
The current DSA code handling switchdev objects does not recurse into
the lower devices thus is never called with an orig_dev member being
a bridge device, hence remove this useless check.

At the same time, remove the comments about the callers, which is
unlikely to be updated if the code changes and thus will be confusing.

Signed-off-by: Vivien Didelot <vivien.didelot@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-14 20:20:07 -07:00
Vladimir Oltean
6358f38c06 net: dsa: tag_sja1105: Select CONFIG_PACKING
The packing facility is needed to decode Ethernet meta frames containing
source port and RX timestamping information.

The DSA driver selects CONFIG_PACKING, but the tagger did not, and since
taggers can be now compiled as modules independently from the drivers
themselves, this is an issue now, as CONFIG_PACKING is disabled by
default on all architectures.

Fixes: e53e18a6fe ("net: dsa: sja1105: Receive and decode meta frames")
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-13 22:42:19 -07:00
Florian Fainelli
2131fba531 net: dsa: Deal with non-existing PHY/fixed-link
We need to specifically deal with phylink_of_phy_connect() returning
-ENODEV, because this can happen when a CPU/DSA port does connect
neither to a PHY, nor has a fixed-link property. This is a valid use
case that is permitted by the binding and indicates to the switch:
auto-configure port with maximum capabilities.

Fixes: 0e27921816 ("net: dsa: Use PHYLINK for the CPU/DSA ports")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-12 11:01:20 -07:00
Vladimir Oltean
f3097be21b net: dsa: sja1105: Add a state machine for RX timestamping
Meta frame reception relies on the hardware keeping its promise that it
will send no other traffic towards the CPU port between a link-local
frame and a meta frame.  Otherwise there is no other way to associate
the meta frame with the link-local frame it's holding a timestamp of.
The receive function is made stateful, and buffers a timestampable frame
until its meta frame arrives, then merges the two, drops the meta and
releases the link-local frame up the stack.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-08 15:20:40 -07:00
Vladimir Oltean
e53e18a6fe net: dsa: sja1105: Receive and decode meta frames
This adds support in the tagger for understanding the source port and
switch id of meta frames.  Their timestamp is also extracted but not
used yet - this needs to be done in a state machine that modifies the
previously received timestampable frame - will be added in a follow-up
patch.

Also take the opportunity to:
- Remove a comment in sja1105_filter made obsolete by e8d67fa569
  ("net: dsa: sja1105: Don't store frame type in skb->cb")
- Reorder the checks in sja1105_filter to optimize for the most likely
  scenario first: regular traffic.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-08 15:20:40 -07:00
Vladimir Oltean
79fa706139 net: dsa: sja1105: Make sja1105_is_link_local not match meta frames
Although meta frames are configured to be sent at SJA1105_META_DMAC
(01-80-C2-00-00-0E) which is a multicast MAC address that would also be
trapped by the switch to the CPU, were it to receive it on a front-panel
port, meta frames are conceptually not link-local frames, they only
carry their RX timestamps.

The choice of sending meta frames at a multicast DMAC is a pragmatic
one, to avoid installing an extra entry to the DSA master port's
multicast MAC filter.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-08 15:20:40 -07:00
Vladimir Oltean
d3f9b90bf1 net: dsa: sja1105: Build a minimal understanding of meta frames
Meta frames are sent on the CPU port by the switch if RX timestamping is
enabled. They contain a partial timestamp of the previous frame.

They are Ethernet frames with the Ethernet header constructed out of:

- SJA1105_META_DMAC
- SJA1105_META_SMAC
- ETH_P_SJA1105_META

The Ethernet payload will be decoded in a follow-up patch.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-08 15:20:40 -07:00
Vladimir Oltean
42824463d3 net: dsa: sja1105: Limit use of incl_srcpt to bridge+vlan mode
The incl_srcpt setting makes the switch mangle the destination MACs of
multicast frames trapped to the CPU - a primitive tagging mechanism that
works even when we cannot use the 802.1Q software features.

The downside is that the two multicast MAC addresses that the switch
traps for L2 PTP (01-80-C2-00-00-0E and 01-1B-19-00-00-00) quickly turn
into a lot more, as the switch encodes the source port and switch id
into bytes 3 and 4 of the MAC. The resulting range of MAC addresses
would need to be installed manually into the DSA master port's multicast
MAC filter, and even then, most devices might not have a large enough
MAC filtering table.

As a result, only limit use of incl_srcpt to when it's strictly
necessary: when under a VLAN filtering bridge.  This fixes PTP in
non-bridged mode (standalone ports). Otherwise, PTP frames, as well as
metadata follow-up frames holding RX timestamps won't be received
because they will be blocked by the master port's MAC filter.
Linuxptp doesn't help, because it only requests the addition of the
unmodified PTP MACs to the multicast filter.
This issue is not seen in bridged mode because the master port is put in
promiscuous mode when the slave ports are enslaved to a bridge.
Therefore, there is no downside to having the incl_srcpt mechanism
active there.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-08 15:20:40 -07:00
Vladimir Oltean
d461933638 net: dsa: tag_8021q: Create helper function for removing VLAN header
This removes the existing implementation from tag_sja1105, which was
partially incorrect (it was not changing the MAC header offset, thereby
leaving it to point 4 bytes earlier than it should have).

This overwrites the VLAN tag by moving the Ethernet source and
destination MACs 4 bytes to the right. Then skb->data (assumed to be
pointing immediately after the EtherType) is temporarily pushed to the
beginning of the new Ethernet header, the new Ethernet header offset and
length are recorded, then skb->data is moved back to where it was.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-08 15:20:39 -07:00
Vladimir Oltean
5e3f847a02 net: dsa: Add teardown callback for drivers
This is helpful for e.g. draining per-driver (not per-port) tagger
queues.

Signed-off-by: Vladimir Oltean <olteanv@gmail.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>
2019-06-08 15:20:39 -07:00
Vladimir Oltean
146d442c23 net: dsa: Keep a pointer to the skb clone for TX timestamping
For drivers that use deferred_xmit for PTP frames (such as sja1105),
there is no need to perform matching between PTP frames and their egress
timestamps, since the sending process can be serialized.

In that case, it makes sense to have the pointer to the skb clone that
DSA made directly in the skb->cb. It will be used for pushing the egress
timestamp back in the application socket's error queue.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-08 15:20:39 -07:00
David S. Miller
a6cdeeb16b Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Some ISDN files that got removed in net-next had some changes
done in mainline, take the removals.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-07 11:00:14 -07:00
Linus Torvalds
1e1d926369 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Free AF_PACKET po->rollover properly, from Willem de Bruijn.

 2) Read SFP eeprom in max 16 byte increments to avoid problems with
    some SFP modules, from Russell King.

 3) Fix UDP socket lookup wrt. VRF, from Tim Beale.

 4) Handle route invalidation properly in s390 qeth driver, from Julian
    Wiedmann.

 5) Memory leak on unload in RDS, from Zhu Yanjun.

 6) sctp_process_init leak, from Neil HOrman.

 7) Fix fib_rules rule insertion semantic change that broke Android,
    from Hangbin Liu.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (33 commits)
  pktgen: do not sleep with the thread lock held.
  net: mvpp2: Use strscpy to handle stat strings
  net: rds: fix memory leak in rds_ib_flush_mr_pool
  ipv6: fix EFAULT on sendto with icmpv6 and hdrincl
  ipv6: use READ_ONCE() for inet->hdrincl as in ipv4
  Revert "fib_rules: return 0 directly if an exactly same rule exists when NLM_F_EXCL not supplied"
  net: aquantia: fix wol configuration not applied sometimes
  ethtool: fix potential userspace buffer overflow
  Fix memory leak in sctp_process_init
  net: rds: fix memory leak when unload rds_rdma
  ipv6: fix the check before getting the cookie in rt6_get_cookie
  ipv4: not do cache for local delivery if bc_forwarding is enabled
  s390/qeth: handle error when updating TX queue count
  s390/qeth: fix VLAN attribute in bridge_hostnotify udev event
  s390/qeth: check dst entry before use
  s390/qeth: handle limited IPv4 broadcast in L3 TX path
  net: fix indirect calls helpers for ptype list hooks.
  net: ipvlan: Fix ipvlan device tso disabled while NETIF_F_IP_CSUM is set
  udp: only choose unbound UDP socket for multicast when not in a VRF
  net/tls: replace the sleeping lock around RX resync with a bit lock
  ...
2019-06-07 09:29:14 -07:00
Vladimir Oltean
e8d67fa569 net: dsa: sja1105: Don't store frame type in skb->cb
Due to a confusion I thought that eth_type_trans() was called by the
network stack whereas it can actually be called by network drivers to
figure out the skb protocol and next packet_type handlers.

In light of the above, it is not safe to store the frame type from the
DSA tagger's .filter callback (first entry point on RX path), since GRO
is yet to be invoked on the received traffic.  Hence it is very likely
that the skb->cb will actually get overwritten between eth_type_trans()
and the actual DSA packet_type handler.

Of course, what this patch fixes is the actual overwriting of the
SJA1105_SKB_CB(skb)->type field from the GRO layer, which made all
frames be seen as SJA1105_FRAME_TYPE_NORMAL (0).

Fixes: 227d07a07e ("net: dsa: sja1105: Add support for traffic through standalone ports")
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-31 14:27:27 -07:00
David S. Miller
b4b12b0d2f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
The phylink conflict was between a bug fix by Russell King
to make sure we have a consistent PHY interface mode, and
a change in net-next to pull some code in phylink_resolve()
into the helper functions phylink_mac_link_{up,down}()

On the dp83867 side it's mostly overlapping changes, with
the 'net' side removing a condition that was supposed to
trigger for RGMII but because of how it was coded never
actually could trigger.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-31 10:49:43 -07:00
Linus Torvalds
2f4c533499 SPDX update for 5.2-rc3, round 1
Here is another set of reviewed patches that adds SPDX tags to different
 kernel files, based on a set of rules that are being used to parse the
 comments to try to determine that the license of the file is
 "GPL-2.0-or-later" or "GPL-2.0-only".  Only the "obvious" versions of
 these matches are included here, a number of "non-obvious" variants of
 text have been found but those have been postponed for later review and
 analysis.
 
 There is also a patch in here to add the proper SPDX header to a bunch
 of Kbuild files that we have missed in the past due to new files being
 added and forgetting that Kbuild uses two different file names for
 Makefiles.  This issue was reported by the Kbuild maintainer.
 
 These patches have been out for review on the linux-spdx@vger mailing
 list, and while they were created by automatic tools, they were
 hand-verified by a bunch of different people, all whom names are on the
 patches are reviewers.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 
 iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCXPCHLg8cZ3JlZ0Brcm9h
 aC5jb20ACgkQMUfUDdst+ykxyACgql6ktH+Tv8Ho1747kKPiFca1Jq0AoK5HORXI
 yB0DSTXYNjMtH41ypnsZ
 =x2f8
 -----END PGP SIGNATURE-----

Merge tag 'spdx-5.2-rc3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull yet more SPDX updates from Greg KH:
 "Here is another set of reviewed patches that adds SPDX tags to
  different kernel files, based on a set of rules that are being used to
  parse the comments to try to determine that the license of the file is
  "GPL-2.0-or-later" or "GPL-2.0-only". Only the "obvious" versions of
  these matches are included here, a number of "non-obvious" variants of
  text have been found but those have been postponed for later review
  and analysis.

  There is also a patch in here to add the proper SPDX header to a bunch
  of Kbuild files that we have missed in the past due to new files being
  added and forgetting that Kbuild uses two different file names for
  Makefiles. This issue was reported by the Kbuild maintainer.

  These patches have been out for review on the linux-spdx@vger mailing
  list, and while they were created by automatic tools, they were
  hand-verified by a bunch of different people, all whom names are on
  the patches are reviewers"

* tag 'spdx-5.2-rc3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (82 commits)
  treewide: Add SPDX license identifier - Kbuild
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 225
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 224
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 223
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 222
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 221
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 220
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 218
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 217
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 216
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 215
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 214
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 213
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 211
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 210
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 209
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 207
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 206
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 203
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 201
  ...
2019-05-31 08:34:32 -07:00
Ioana Ciornei
e70c7aad7a net: dsa: Add error path handling in dsa_tree_setup()
In case a call to dsa_tree_setup() fails, an attempt to cleanup is made
by calling dsa_tree_remove_switch(), which should take care of
removing/unregistering any resources previously allocated. This does not
happen because it is conditioned by dst->setup being true, which is set
only after _all_ setup steps were performed successfully.

This is especially interesting when the internal MDIO bus is registered
but afterwards, a port setup fails and the mdiobus_unregister() is never
called. This leads to a BUG_ON() complaining about the fact that it's
trying to free an MDIO bus that's still registered.

Add proper error handling in all functions branching from
dsa_tree_setup().

Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Reported-by: kernel test robot <rong.a.chen@intel.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-30 14:58:31 -07:00
Vladimir Oltean
0471dd429c net: dsa: tag_8021q: Create a stable binary format
Tools like tcpdump need to be able to decode the significance of fake
VLAN headers that DSA uses to separate switch ports.

But currently these have no global significance - they are simply an
ordered list of DSA_MAX_SWITCHES x DSA_MAX_PORTS numbers ending at 4095.

The reason why this is submitted as a fix is that the existing mapping
of VIDs should not enter into a stable kernel, so we can pretend that
only the new format exists. This way tcpdump won't need to try to make
something out of the VLAN tags on 5.2 kernels.

Fixes: f9bbe4477c ("net: dsa: Optional VLAN-based port separation for switches without tagging")
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-30 14:47:14 -07:00
Ioana Ciornei
d34d2baa91 net: dsa: tag_8021q: Change order of rx_vid setup
The 802.1Q tagging performs an unbalanced setup in terms of RX VIDs on
the CPU port. For the ingress path of a 802.1Q switch to work, the RX
VID of a port needs to be seen as tagged egress on the CPU port.

While configuring the other front-panel ports to be part of this VID,
for bridge scenarios, the untagged flag is applied even on the CPU port
in dsa_switch_vlan_add.  This happens because DSA applies the same flags
on the CPU port as on the (bridge-controlled) slave ports, and the
effect in this case is that the CPU port tagged settings get deleted.

Instead of fixing DSA by introducing a way to control VLAN flags on the
CPU port (and hence stop inheriting from the slave ports) - a hard,
perhaps intractable problem - avoid this situation by moving the setup
part of the RX VID on the CPU port after all the other front-panel ports
have been added to the VID.

Fixes: f9bbe4477c ("net: dsa: Optional VLAN-based port separation for switches without tagging")
Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-30 14:47:14 -07:00
Thomas Gleixner
2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00
Ioana Ciornei
0e27921816 net: dsa: Use PHYLINK for the CPU/DSA ports
For DSA switches that do not have an .adjust_link callback, aka those
who transitioned totally to the PHYLINK-compliant API, use PHYLINK to
drive the CPU/DSA ports.

The PHYLIB usage and .adjust_link are kept but deprecated, and users are
asked to transition from it.  The reason why we can't do anything for
them is because PHYLINK does not wrap the fixed-link state behind a
phydev object, so we cannot wrap .phylink_mac_config into .adjust_link
unless we fabricate a phy_device structure.

For these ports, the newly introduced PHYLINK_DEV operation type is
used and the dsa_switch device structure is passed to PHYLINK for
printing purposes.  The handling of the PHYLINK_NETDEV and PHYLINK_DEV
PHYLINK instances is common from the perspective of the driver.

Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-29 21:48:53 -07:00
Ioana Ciornei
77373d49de net: dsa: Move the phylink driver calls into port.c
In order to have a common handling of PHYLINK for the slave and non-user
ports, the DSA core glue logic (between PHYLINK and the driver) must use
an API that does not rely on a struct net_device.

These will also be called by the CPU-port-handling code in a further
patch.

Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Suggested-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-29 21:48:53 -07:00
Ioana Ciornei
44cc27e43f net: phylink: Add struct phylink_config to PHYLINK API
The phylink_config structure will encapsulate a pointer to a struct
device and the operation type requested for this instance of PHYLINK.
This patch does not make any functional changes, it just transitions the
PHYLINK internals and all its users to the new API.

A pointer to a phylink_config structure will be passed to
phylink_create() instead of the net_device directly. Also, the same
phylink_config pointer will be passed back to all phylink_mac_ops
callbacks instead of the net_device. Using this mechanism, a PHYLINK
user can get the original net_device using a structure such as
'to_net_dev(config->dev)' or directly the structure containing the
phylink_config using a container_of call.

At the moment, only the PHYLINK_NETDEV is defined as a valid operation
type for PHYLINK. In this mode, a valid reference to a struct device
linked to the original net_device should be passed to PHYLINK through
the phylink_config structure.

This API changes is mainly driven by the necessity of adding a new
operation type in PHYLINK that disconnects the phy_device from the
net_device and also works when the net_device is lacking.

Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Tested-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-29 21:48:53 -07:00
Thomas Gleixner
ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Vladimir Oltean
8767137510 net: dsa: Initialize DSA_SKB_CB(skb)->deferred_xmit variable
The sk_buff control block can have any contents on xmit put there by the
stack, so initialization is mandatory, since we are checking its value
after the actual DSA xmit (the tagger may have changed it).

The DSA_SKB_ZERO() macro could have been used for this purpose, but:
- Zeroizing a 48-byte memory region in the hotpath is best avoided.
- It would have triggered a warning with newer compilers since
  __dsa_skb_cb contains a structure within a structure, and the {0}
  initializer was incorrect for that purpose.

So simply remove the DSA_SKB_ZERO() macro and initialize the
deferred_xmit variable by hand (which should be done for all further
dsa_skb_cb variables which need initialization - currently none - to
avoid the performance penalty).

Fixes: 97a69a0dea ("net: dsa: Add support for deferred xmit")
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-12 13:19:46 -07:00
YueHaibing
b96a54154b dsa: tag_brcm: Fix build error without CONFIG_NET_DSA_TAG_BRCM_PREPEND
Fix gcc build error:

net/dsa/tag_brcm.c:211:16: error: brcm_prepend_netdev_ops undeclared here (not in a function); did you mean brcm_netdev_ops?
 DSA_TAG_DRIVER(brcm_prepend_netdev_ops);
                ^
./include/net/dsa.h:708:10: note: in definition of macro DSA_TAG_DRIVER
  .ops = &__ops,       \
          ^~~~~
./include/net/dsa.h:701:36: warning: dsa_tag_driver_brcm_prepend_netdev_ops defined but not used [-Wunused-variable]
 #define DSA_TAG_DRIVER_NAME(__ops) dsa_tag_driver ## _ ## __ops
                                    ^
./include/net/dsa.h:707:30: note: in expansion of macro DSA_TAG_DRIVER_NAME
 static struct dsa_tag_driver DSA_TAG_DRIVER_NAME(__ops) = {  \
                              ^~~~~~~~~~~~~~~~~~~
net/dsa/tag_brcm.c:211:1: note: in expansion of macro DSA_TAG_DRIVER
 DSA_TAG_DRIVER(brcm_prepend_netdev_ops);

Like the CONFIG_NET_DSA_TAG_BRCM case,
brcm_prepend_netdev_ops and DSA_TAG_PROTO_BRCM_PREPEND
should be wrappeed by CONFIG_NET_DSA_TAG_BRCM_PREPEND.

Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: b74b70c449 ("net: dsa: Support prepended Broadcom tag")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-10 15:06:45 -07:00
David S. Miller
a9e41a5296 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Minor conflict with the DSA legacy code removal.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-07 17:22:09 -07:00
Petr Štetiar
4974f9b7e0 net: dsa: support of_get_mac_address new ERR_PTR error
There was NVMEM support added to of_get_mac_address, so it could now
return ERR_PTR encoded error values, so we need to adjust all current
users of of_get_mac_address to this new fact.

While at it, remove superfluous is_valid_ether_addr as the MAC address
returned from of_get_mac_address is always valid and checked by
is_valid_ether_addr anyway.

Fixes: d01f449c00 ("of_net: add NVMEM support to of_get_mac_address")
Signed-off-by: Petr Štetiar <ynezz@true.cz>
Tested-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-07 12:22:47 -07:00
YueHaibing
68be930249 net: dsa: Fix error cleanup path in dsa_init_module
BUG: unable to handle kernel paging request at ffffffffa01c5430
PGD 3270067 P4D 3270067 PUD 3271063 PMD 230bc5067 PTE 0
Oops: 0000 [#1
CPU: 0 PID: 6159 Comm: modprobe Not tainted 5.1.0+ #33
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org 04/01/2014
RIP: 0010:raw_notifier_chain_register+0x16/0x40
Code: 63 f8 66 90 e9 5d ff ff ff 90 90 90 90 90 90 90 90 90 90 90 55 48 8b 07 48 89 e5 48 85 c0 74 1c 8b 56 10 3b 50 10 7e 07 eb 12 <39> 50 10 7c 0d 48 8d 78 08 48 8b 40 08 48 85 c0 75 ee 48 89 46 08
RSP: 0018:ffffc90001c33c08 EFLAGS: 00010282
RAX: ffffffffa01c5420 RBX: ffffffffa01db420 RCX: 4fcef45928070a8b
RDX: 0000000000000000 RSI: ffffffffa01db420 RDI: ffffffffa01b0068
RBP: ffffc90001c33c08 R08: 000000003e0a33d0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000094443661 R12: ffff88822c320700
R13: ffff88823109be80 R14: 0000000000000000 R15: ffffc90001c33e78
FS:  00007fab8bd08540(0000) GS:ffff888237a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffa01c5430 CR3: 00000002297ea000 CR4: 00000000000006f0
Call Trace:
 register_netdevice_notifier+0x43/0x250
 ? 0xffffffffa01e0000
 dsa_slave_register_notifier+0x13/0x70 [dsa_core
 ? 0xffffffffa01e0000
 dsa_init_module+0x2e/0x1000 [dsa_core
 do_one_initcall+0x6c/0x3cc
 ? do_init_module+0x22/0x1f1
 ? rcu_read_lock_sched_held+0x97/0xb0
 ? kmem_cache_alloc_trace+0x325/0x3b0
 do_init_module+0x5b/0x1f1
 load_module+0x1db1/0x2690
 ? m_show+0x1d0/0x1d0
 __do_sys_finit_module+0xc5/0xd0
 __x64_sys_finit_module+0x15/0x20
 do_syscall_64+0x6b/0x1d0
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Cleanup allocated resourses if there are errors,
otherwise it will trgger memleak.

Fixes: c9eb3e0f87 ("net: dsa: Add support for learning FDB through notification")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-07 12:17:23 -07:00
Vladimir Oltean
227d07a07e net: dsa: sja1105: Add support for traffic through standalone ports
In order to support this, we are creating a make-shift switch tag out of
a VLAN trunk configured on the CPU port. Termination of normal traffic
on switch ports only works when not under a vlan_filtering bridge.
Termination of management (PTP, BPDU) traffic works under all
circumstances because it uses a different tagging mechanism
(incl_srcpt). We are making use of the generic CONFIG_NET_DSA_TAG_8021Q
code and leveraging it from our own CONFIG_NET_DSA_TAG_SJA1105.

There are two types of traffic: regular and link-local.

The link-local traffic received on the CPU port is trapped from the
switch's regular forwarding decisions because it matched one of the two
DMAC filters for management traffic.

On transmission, the switch requires special massaging for these
link-local frames. Due to a weird implementation of the switching IP, by
default it drops link-local frames that originate on the CPU port.
It needs to be told where to forward them to, through an SPI command
("management route") that is valid for only a single frame.
So when we're sending link-local traffic, we are using the
dsa_defer_xmit mechanism.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-05 21:52:42 -07:00
Vladimir Oltean
97a69a0dea net: dsa: Add support for deferred xmit
Some hardware needs to take work to get convinced to receive frames on
the CPU port (such as the sja1105 which takes temporary L2 forwarding
rules over SPI that last for a single frame). Such work needs a
sleepable context, and because the regular .ndo_start_xmit is atomic,
this cannot be done in the tagger. So introduce a generic DSA mechanism
that sets up a transmit skb queue and a workqueue for deferred
transmission.

The new driver callback (.port_deferred_xmit) is in dsa_switch and not
in the tagger because the operations that require sleeping typically
also involve interacting with the hardware, and not simply skb
manipulations. Therefore having it there simplifies the structure a bit
and makes it unnecessary to export functions from the driver to the
tagger.

The driver is responsible of calling dsa_enqueue_skb which transfers it
to the master netdevice. This is so that it has a chance of performing
some more work afterwards, such as cleanup or TX timestamping.

To tell DSA that skb xmit deferral is required, I have thought about
changing the return type of the tagger .xmit from struct sk_buff * into
a enum dsa_tx_t that could potentially encode a DSA_XMIT_DEFER value.

But the trailer tagger is reallocating every skb on xmit and therefore
making a valid use of the pointer return value. So instead of reworking
the API in complicated ways, right now a boolean property in the newly
introduced DSA_SKB_CB is set.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-05 21:52:42 -07:00
Vladimir Oltean
cc1939e4b3 net: dsa: Allow drivers to filter packets they can decode source port from
Frames get processed by DSA and redirected to switch port net devices
based on the ETH_P_XDSA multiplexed packet_type handler found by the
network stack when calling eth_type_trans().

The running assumption is that once the DSA .rcv function is called, DSA
is always able to decode the switch tag in order to change the skb->dev
from its master.

However there are tagging protocols (such as the new DSA_TAG_PROTO_SJA1105,
user of DSA_TAG_PROTO_8021Q) where this assumption is not completely
true, since switch tagging piggybacks on the absence of a vlan_filtering
bridge. Moreover, management traffic (BPDU, PTP) for this switch doesn't
rely on switch tagging, but on a different mechanism. So it would make
sense to at least be able to terminate that.

Having DSA receive traffic it can't decode would put it in an impossible
situation: the eth_type_trans() function would invoke the DSA .rcv(),
which could not change skb->dev, then eth_type_trans() would be invoked
again, which again would call the DSA .rcv, and the packet would never
be able to exit the DSA filter and would spiral in a loop until the
whole system dies.

This happens because eth_type_trans() doesn't actually look at the skb
(so as to identify a potential tag) when it deems it as being
ETH_P_XDSA. It just checks whether skb->dev has a DSA private pointer
installed (therefore it's a DSA master) and that there exists a .rcv
callback (everybody except DSA_TAG_PROTO_NONE has that). This is
understandable as there are many switch tags out there, and exhaustively
checking for all of them is far from ideal.

The solution lies in introducing a filtering function for each tagging
protocol. In the absence of a filtering function, all traffic is passed
to the .rcv DSA callback. The tagging protocol should see the filtering
function as a pre-validation that it can decode the incoming skb. The
traffic that doesn't match the filter will bypass the DSA .rcv callback
and be left on the master netdevice, which wasn't previously possible.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-05 21:52:42 -07:00
Vladimir Oltean
f9bbe4477c net: dsa: Optional VLAN-based port separation for switches without tagging
This patch provides generic DSA code for using VLAN (802.1Q) tags for
the same purpose as a dedicated switch tag for injection/extraction.
It is based on the discussions and interest that has been so far
expressed in https://www.spinics.net/lists/netdev/msg556125.html.

Unlike all other DSA-supported tagging protocols, CONFIG_NET_DSA_TAG_8021Q
does not offer a complete solution for drivers (nor can it). Instead, it
provides generic code that driver can opt into calling:
- dsa_8021q_xmit: Inserts a VLAN header with the specified contents.
  Can be called from another tagging protocol's xmit function.
  Currently the LAN9303 driver is inserting headers that are simply
  802.1Q with custom fields, so this is an opportunity for code reuse.
- dsa_8021q_rcv: Retrieves the TPID and TCI from a VLAN-tagged skb.
  Removing the VLAN header is left as a decision for the caller to make.
- dsa_port_setup_8021q_tagging: For each user port, installs an Rx VID
  and a Tx VID, for proper untagged traffic identification on ingress
  and steering on egress. Also sets up the VLAN trunk on the upstream
  (CPU or DSA) port. Drivers are intentionally left to call this
  function explicitly, depending on the context and hardware support.
  The expected switch behavior and VLAN semantics should not be violated
  under any conditions. That is, after calling
  dsa_port_setup_8021q_tagging, the hardware should still pass all
  ingress traffic, be it tagged or untagged.

For uniformity with the other tagging protocols, a module for the
dsa_8021q_netdev_ops structure is registered, but the typical usage is
to set up another tagging protocol which selects CONFIG_NET_DSA_TAG_8021Q,
and calls the API from tag_8021q.h. Null function definitions are also
provided so that a "depends on" is not forced in the Kconfig.

This tagging protocol only works when switch ports are standalone, or
when they are added to a VLAN-unaware bridge. It will probably remain
this way for the reasons below.

When added to a bridge that has vlan_filtering 1, the bridge core will
install its own VLANs and reset the pvids through switchdev. For the
bridge core, switchdev is a write-only pipe. All VLAN-related state is
kept in the bridge core and nothing is read from DSA/switchdev or from
the driver. So the bridge core will break this port separation because
it will install the vlan_default_pvid into all switchdev ports.

Even if we could teach the bridge driver about switchdev preference of a
certain vlan_default_pvid (task difficult in itself since the current
setting is per-bridge but we would need it per-port), there would still
exist many other challenges.

Firstly, in the DSA rcv callback, a driver would have to perform an
iterative reverse lookup to find the correct switch port. That is
because the port is a bridge slave, so its Rx VID (port PVID) is subject
to user configuration. How would we ensure that the user doesn't reset
the pvid to a different value (which would make an O(1) translation
impossible), or to a non-unique value within this DSA switch tree (which
would make any translation impossible)?

Finally, not all switch ports are equal in DSA, and that makes it
difficult for the bridge to be completely aware of this anyway.
The CPU port needs to transmit tagged packets (VLAN trunk) in order for
the DSA rcv code to be able to decode source information.
But the bridge code has absolutely no idea which switch port is the CPU
port, if nothing else then just because there is no netdevice registered
by DSA for the CPU port.
Also DSA does not currently allow the user to specify that they want the
CPU port to do VLAN trunking anyway. VLANs are added to the CPU port
using the same flags as they were added on the user port.

So the VLANs installed by dsa_port_setup_8021q_tagging per driver
request should remain private from the bridge's and user's perspective,
and should not alter the VLAN semantics observed by the user.

In the current implementation a VLAN range ending at 4095 (VLAN_N_VID)
is reserved for this purpose. Each port receives a unique Rx VLAN and a
unique Tx VLAN. Separate VLANs are needed for Rx and Tx because they
serve different purposes: on Rx the switch must process traffic as
untagged and process it with a port-based VLAN, but with care not to
hinder bridging. On the other hand, the Tx VLAN is where the
reachability restrictions are imposed, since by tagging frames in the
xmit callback we are telling the switch onto which port to steer the
frame.

Some general guidance on how this support might be employed for
real-life hardware (some comments made by Florian Fainelli):

- If the hardware supports VLAN tag stacking, it should somehow back
  up its private VLAN settings when the bridge tries to override them.
  Then the driver could re-apply them as outer tags. Dedicating an outer
  tag per bridge device would allow identical inner tag VID numbers to
  co-exist, yet preserve broadcast domain isolation.

- If the switch cannot handle VLAN tag stacking, it should disable this
  port separation when added as slave to a vlan_filtering bridge, in
  that case having reduced functionality.

- Drivers for old switches that don't support the entire VLAN_N_VID
  range will need to rework the current range selection mechanism.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-05 21:52:42 -07:00