Currently, ocelot switchdev passes the skb directly to the function that
enqueues it to the list of skb's awaiting a TX timestamp. Whereas the
felix DSA driver first clones the skb, then passes the clone to this
queue.

This matters because in the case of felix, the common IRQ handler, which
is ocelot_get_txtstamp(), currently clones the clone, and frees the
original clone. This is useless and can be simplified by using
skb_complete_tx_timestamp() instead of skb_tstamp_tx().
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: NRichard Cochran <richardcochran@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Update the B53 driver to support VLANs while not filtering. This
requires us to enable VLAN globally within the switch upon driver
initial configuration (dev->vlan_enabled).

We also need to remove the code that dealt with PVID re-configuration in
b53_vlan_filtering() since that function worked under the assumption
that it would only be called to make a bridge VLAN filtering, or not
filtering, and we would attempt to move the port's PVID accordingly.

Now that VLANs are programmed all the time, even in the case of a
non-VLAN filtering bridge, we would be programming a default_pvid for
the bridged switch ports.

We need the DSA receive path to pop the VLAN tag if it is the bridge's
default_pvid because the CPU port is always programmed tagged in the
programmed VLANs. In order to do so we utilize the
dsa_untag_bridge_pvid() helper introduced in the commit before within
net/dsa/tag_brcm.c.
Acked-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently the bridge untags VLANs present in its VLAN groups in
__allowed_ingress() only when VLAN filtering is enabled.

But when a skb is seen on the RX path as tagged with the bridge's pvid,
and that bridge has vlan_filtering=0, and there isn't any 8021q upper
with that VLAN either, then we have a problem. The bridge will not untag
it (since it is supposed to remain VLAN-unaware), and pvid-tagged
communication will be broken.

There are 2 situations where we can end up like that:

1. When installing a pvid in egress-tagged mode, like this:

ip link add dev br0 type bridge vlan_filtering 0
ip link set swp0 master br0
bridge vlan del dev swp0 vid 1
bridge vlan add dev swp0 vid 1 pvid

This happens because DSA configures the VLAN membership of the CPU port
using the same flags as swp0 (in this case "pvid and not untagged"), in
an attempt to copy the frame as-is from ingress to the CPU.

However, in this case, the packet may arrive untagged on ingress, it
will be pvid-tagged by the ingress port, and will be sent as
egress-tagged towards the CPU. Otherwise stated, the CPU will see a VLAN
tag where there was none to speak of on ingress.

When vlan_filtering is 1, this is not a problem, as stated in the first
paragraph, because __allowed_ingress() will pop it. But currently, when
vlan_filtering is 0 and we have such a VLAN configuration, we need an
8021q upper (br0.1) to be able to ping over that VLAN, which is not
symmetrical with the vlan_filtering=1 case, and therefore, confusing for
users.

Basically what DSA attempts to do is simply an approximation: try to
copy the skb with (or without) the same VLAN all the way up to the CPU.
But DSA drivers treat CPU port VLAN membership in various ways (which is
a good segue into situation 2). And some of those drivers simply tell
the CPU port to copy the frame unmodified, which is the golden standard
when it comes to VLAN processing (therefore, any driver which can
configure the hardware to do that, should do that, and discard the VLAN
flags requested by DSA on the CPU port).

2. Some DSA drivers always configure the CPU port as egress-tagged, in
an attempt to recover the classified VLAN from the skb. These drivers
cannot work at all with untagged traffic when bridged in
vlan_filtering=0 mode. And they can't go for the easy "just keep the
pvid as egress-untagged towards the CPU" route, because each front port
can have its own pvid, and that might require conflicting VLAN
membership settings on the CPU port (swp1 is pvid for VID 1 and
egress-tagged for VID 2; swp2 is egress-taggeed for VID 1 and pvid for
VID 2; with this simplistic approach, the CPU port, which is really a
separate hardware entity and has its own VLAN membership settings, would
end up being egress-untagged in both VID 1 and VID 2, therefore losing
the VLAN tags of ingress traffic).

So the only thing we can do is to create a helper function for resolving
the problematic case (that is, a function which untags the bridge pvid
when that is in vlan_filtering=0 mode), which taggers in need should
call. It isn't called from the generic DSA receive path because there
are drivers that fall neither in the first nor second category.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

kernel-doc expects the function prototype to be just after
the kernel-doc markup, as otherwise it will get it all wrong:

	./net/core/dev.c:10036: warning: Excess function parameter 'dev' description in 'WAIT_REFS_MIN_MSECS'

Fixes: 0e4be9e5 ("net: use exponential backoff in netdev_wait_allrefs")
Signed-off-by: NMauro Carvalho Chehab <mchehab+huawei@kernel.org>
Reviewed-by: NFrancesco Ruggeri <fruggeri@arista.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We need to avoid forwarding to ports in MCAST_INCLUDE filter mode when the
mdst entry is a *,G or when the port has the blocked flag.
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since host joins are considered as EXCLUDE {} joins we need to reflect
that in all of *,G ports' S,G entries. Since the S,Gs can have
host_joined == true only set automatically we can safely set it to false
when removing all automatically added entries upon S,G delete.
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When excluding S,G entries we need a way to block a particular S,G,port.
The new port group flag is managed based on the source's timer as per
RFCs 3376 and 3810. When a source expires and its port group is in
EXCLUDE mode, it will be blocked.
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We need to handle group filter mode transitions and initial state.
To change a port group's INCLUDE -> EXCLUDE mode (or when we have added
a new port group in EXCLUDE mode) we need to add that port to all of
*,G ports' S,G entries for proper replication. When the EXCLUDE state is
changed from IGMPv3 report, br_multicast_fwd_filter_exclude() must be
called after the source list processing because the assumption is that
all of the group's S,G entries will be created before transitioning to
EXCLUDE mode, i.e. most importantly its blocked entries will already be
added so it will not get automatically added to them.
The transition EXCLUDE -> INCLUDE happens only when a port group timer
expires, it requires us to remove that port from all of *,G ports' S,G
entries where it was automatically added previously.
Finally when we are adding a new S,G entry we must add all of *,G's
EXCLUDE ports to it.
In order to distinguish automatically added *,G EXCLUDE ports we have a
new port group flag - MDB_PG_FLAGS_STAR_EXCL.
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds support for automatic install of S,G mdb entries based
on the port group's source list and the source entry's timer.
Once installed the S,G will be used when forwarding packets if the
approprate multicast/mld versions are set. A new source flag called
BR_SGRP_F_INSTALLED denotes if the source has a forwarding mdb entry
installed.
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

To speedup S,G forward handling we need to be able to quickly find out
if a port is a member of an S,G group. To do that add a global S,G port
rhashtable with key: source addr, group addr, protocol, vid (all br_ip
fields) and port pointer.
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We need to be able to differentiate between pg entries created by
user-space and the kernel when we start generating S,G entries for
IGMPv3/MLDv2's fast path. User-space entries are created by default as
RTPROT_STATIC and the kernel entries are RTPROT_KERNEL. Later we can
allow user-space to provide the entry rt_protocol so we can
differentiate between who added the entries specifically (e.g. clag,
admin, frr etc).
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If (S,G) entries are enabled (igmpv3/mldv2) then look them up first. If
there isn't a present (S,G) entry then try to find (*,G).
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add new mdb attributes (MDBE_ATTR_SOURCE for setting,
MDBA_MDB_EATTR_SOURCE for dumping) to allow add/del and dump of mdb
entries with a source address (S,G). New S,G entries are created with
filter mode of MCAST_INCLUDE. The same attributes are used for IPv4 and
IPv6, they're validated and parsed based on their protocol.
S,G host joined entries which are added by user are not allowed yet.
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since the MDB add/del code expects an exact struct br_mdb_entry we can't
really add any extensions, thus add a new nested attribute at the level of
MDBA_SET_ENTRY called MDBA_SET_ENTRY_ATTRS which will be used to pass
all new options via netlink attributes. This patch doesn't change
anything functionally since the new attribute is not used yet, only
parsed.
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since now we have src in br_ip, u no longer makes sense so rename
it to dst. No functional changes.

v2: fix build with CONFIG_BATMAN_ADV_MCAST

CC: Marek Lindner <mareklindner@neomailbox.ch>
CC: Simon Wunderlich <sw@simonwunderlich.de>
CC: Antonio Quartulli <a@unstable.cc>
CC: Sven Eckelmann <sven@narfation.org>
CC: b.a.t.m.a.n@lists.open-mesh.org
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that we have src and dst in br_ip it is logical to use the src field
for the cases where we need to work with a source address such as
querier source address and group source address.
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pass and use extack all the way down to br_mdb_add_group().
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

To avoid doing duplicate device checks and searches (the same were done
in br_mdb_add and __br_mdb_add) pass the already found port to __br_mdb_add
and pull the bridge's netif_running and enabled multicast checks to
br_mdb_add. This would also simplify the future extack errors.
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We can drop the pr_info() calls and just use extack to return a
meaningful error to user-space when br_mdb_parse() fails.
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use range checking facility of nla_policy to validate port type
attribute input value is valid or not.
Signed-off-by: NParav Pandit <parav@nvidia.com>
Reviewed-by: NJiri Pirko <jiri@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use range checking facility of nla_policy to validate eswitch mode input
attribute value is valid or not.
Signed-off-by: NParav Pandit <parav@nvidia.com>
Reviewed-by: NJiri Pirko <jiri@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

User space could send an invalid INET_DIAG_REQ_PROTOCOL attribute
as caught by syzbot.

BUG: KMSAN: uninit-value in inet_diag_lock_handler net/ipv4/inet_diag.c:55 [inline]
BUG: KMSAN: uninit-value in __inet_diag_dump+0x58c/0x720 net/ipv4/inet_diag.c:1147
CPU: 0 PID: 8505 Comm: syz-executor174 Not tainted 5.9.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x21c/0x280 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:122
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:219
 inet_diag_lock_handler net/ipv4/inet_diag.c:55 [inline]
 __inet_diag_dump+0x58c/0x720 net/ipv4/inet_diag.c:1147
 inet_diag_dump_compat+0x2a5/0x380 net/ipv4/inet_diag.c:1254
 netlink_dump+0xb73/0x1cb0 net/netlink/af_netlink.c:2246
 __netlink_dump_start+0xcf2/0xea0 net/netlink/af_netlink.c:2354
 netlink_dump_start include/linux/netlink.h:246 [inline]
 inet_diag_rcv_msg_compat+0x5da/0x6c0 net/ipv4/inet_diag.c:1288
 sock_diag_rcv_msg+0x24f/0x620 net/core/sock_diag.c:256
 netlink_rcv_skb+0x6d7/0x7e0 net/netlink/af_netlink.c:2470
 sock_diag_rcv+0x63/0x80 net/core/sock_diag.c:275
 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline]
 netlink_unicast+0x11c8/0x1490 net/netlink/af_netlink.c:1330
 netlink_sendmsg+0x173a/0x1840 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg net/socket.c:671 [inline]
 ____sys_sendmsg+0xc82/0x1240 net/socket.c:2353
 ___sys_sendmsg net/socket.c:2407 [inline]
 __sys_sendmsg+0x6d1/0x820 net/socket.c:2440
 __do_sys_sendmsg net/socket.c:2449 [inline]
 __se_sys_sendmsg+0x97/0xb0 net/socket.c:2447
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2447
 do_syscall_64+0x9f/0x140 arch/x86/entry/common.c:48
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x441389
Code: e8 fc ab 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 1b 09 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fff3b02ce98 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441389
RDX: 0000000000000000 RSI: 0000000020001500 RDI: 0000000000000003
RBP: 00000000006cb018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000402130
R13: 00000000004021c0 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:143 [inline]
 kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:126
 kmsan_slab_alloc+0x8a/0xe0 mm/kmsan/kmsan_hooks.c:80
 slab_alloc_node mm/slub.c:2907 [inline]
 __kmalloc_node_track_caller+0x9aa/0x12f0 mm/slub.c:4511
 __kmalloc_reserve net/core/skbuff.c:142 [inline]
 __alloc_skb+0x35f/0xb30 net/core/skbuff.c:210
 alloc_skb include/linux/skbuff.h:1094 [inline]
 netlink_alloc_large_skb net/netlink/af_netlink.c:1176 [inline]
 netlink_sendmsg+0xdb9/0x1840 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg net/socket.c:671 [inline]
 ____sys_sendmsg+0xc82/0x1240 net/socket.c:2353
 ___sys_sendmsg net/socket.c:2407 [inline]
 __sys_sendmsg+0x6d1/0x820 net/socket.c:2440
 __do_sys_sendmsg net/socket.c:2449 [inline]
 __se_sys_sendmsg+0x97/0xb0 net/socket.c:2447
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2447
 do_syscall_64+0x9f/0x140 arch/x86/entry/common.c:48
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: 3f935c75 ("inet_diag: support for wider protocol numbers")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Christoph Paasch <cpaasch@apple.com>
Cc: Mat Martineau <mathew.j.martineau@linux.intel.com>
Acked-by: NPaolo Abeni <pabeni@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When calling the RCU brother of br_vlan_get_pvid(), lockdep warns:

=============================
WARNING: suspicious RCU usage
5.9.0-rc3-01631-g13c17acb8e38-dirty #814 Not tainted
-----------------------------
net/bridge/br_private.h:1054 suspicious rcu_dereference_protected() usage!

Call trace:
 lockdep_rcu_suspicious+0xd4/0xf8
 __br_vlan_get_pvid+0xc0/0x100
 br_vlan_get_pvid_rcu+0x78/0x108

The warning is because br_vlan_get_pvid_rcu() calls nbp_vlan_group()
which calls rtnl_dereference() instead of rcu_dereference(). In turn,
rtnl_dereference() calls rcu_dereference_protected() which assumes
operation under an RCU write-side critical section, which obviously is
not the case here. So, when the incorrect primitive is used to access
the RCU-protected VLAN group pointer, READ_ONCE() is not used, which may
cause various unexpected problems.

I'm sad to say that br_vlan_get_pvid() and br_vlan_get_pvid_rcu() cannot
share the same implementation. So fix the bug by splitting the 2
functions, and making br_vlan_get_pvid_rcu() retrieve the VLAN groups
under proper locking annotations.

Fixes: 7582f5b7 ("bridge: add br_vlan_get_pvid_rcu()")
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If a bucket contains a lot of sockets, during bpf_iter traversing
a bucket, concurrent userspace bpf_map_update_elem() and
bpf program bpf_sk_storage_{get,delete}() may experience
some undesirable delays as they will compete with bpf_iter
for bucket lock.

Note that the number of buckets for bpf_sk_storage_map
is roughly the same as the number of cpus. So if there
are lots of sockets in the system, each bucket could
contain lots of sockets.

Different actual use cases may experience different delays.
Here, using selftest bpf_iter subtest bpf_sk_storage_map,
I hacked the kernel with ktime_get_mono_fast_ns()
to collect the time when a bucket was locked
during bpf_iter prog traversing that bucket. This way,
the maximum incurred delay was measured w.r.t. the
number of elements in a bucket.
    # elems in each bucket          delay(ns)
      64                            17000
      256                           72512
      2048                          875246

The potential delays will be further increased if
we have even more elemnts in a bucket. Using rcu_read_lock()
is a reasonable compromise here. It may lose some precision, e.g.,
access stale sockets, but it will not hurt performance of
bpf program or user space application which also tries
to get/delete or update map elements.
Signed-off-by: NYonghong Song <yhs@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NSong Liu <songliubraving@fb.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200916224645.720172-1-yhs@fb.com

Function prototypes using ARG_PTR_TO_BTF_ID currently use two ways to signal
which BTF IDs are acceptable. First, bpf_func_proto.btf_id is an array of
IDs, one for each argument. This array is only accessed up to the highest
numbered argument that uses ARG_PTR_TO_BTF_ID and may therefore be less than
five arguments long. It usually points at a BTF_ID_LIST. Second, check_btf_id
is a function pointer that is called by the verifier if present. It gets the
actual BTF ID of the register, and the argument number we're currently checking.
It turns out that the only user check_arg_btf_id ignores the argument, and is
simply used to check whether the BTF ID has a struct sock_common at it's start.

Replace both of these mechanisms with an explicit BTF ID for each argument
in a function proto. Thanks to btf_struct_ids_match this is very flexible:
check_arg_btf_id can be replaced by requiring struct sock_common.
Signed-off-by: NLorenz Bauer <lmb@cloudflare.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200921121227.255763-5-lmb@cloudflare.com

Replace a comma between expression statements by a semicolon.
Signed-off-by: NXu Wang <vulab@iscas.ac.cn>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

After commit 37ab4fa7 ("net: unix: allow bind to fail on mutex lock"),
the assignment to err is redundant. So remove it.
Signed-off-by: NJing Xiangfeng <jingxiangfeng@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently the backlog status in not exposed to user-space.
Since long backlogs (or simply not empty ones) can be a
source of noticeable latency, -RT deployments need some way
to inspect it.

Additionally, there isn't a direct match between 'softnet_stat'
lines and the related CPU - sd for offline CPUs are not dumped -
so this patch also includes the CPU id into such entry.
Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The "WITH Linux-syscall-note" exception is intended for UAPI headers.

See LICENSES/exceptions/Linux-syscall-note
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/r/20200403073741.18352-1-masahiroy@kernel.orgAcked-by: NOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch fixes the indention to follow kernel coding style.

Link: https://lore.kernel.org/r/20200915223527.1417033-7-mkl@pengutronix.deSigned-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch fixes spelling erros found by "codespell" in the net/can
subtree.

Link: https://lore.kernel.org/r/20200915223527.1417033-5-mkl@pengutronix.deSigned-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

sg_init_table zeroes its first argument, so the allocation of that argument
doesn't have to.

the semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression x,n,flags;
@@

x =
- kcalloc
+ kmalloc_array
  (n,sizeof(*x),flags)
...
sg_init_table(x,n)
// </smpl>
Signed-off-by: NJulia Lawall <Julia.Lawall@inria.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Check whether there is any hwaccel VLAN tag on RX, and if there is,
treat it as the tag_8021q header.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The whole purpose of tag_8021q is to send VLAN-tagged traffic to the
CPU, from which the driver can decode the source port and switch id.

Currently this only works if the VLAN filtering on the master is
disabled. Change that by explicitly adding code to tag_8021q.c to add
the VLANs corresponding to the tags to the filter of the master
interface.

Because we now need to call vlan_vid_add, then we also need to hold the
RTNL mutex. Propagate that requirement to the callers of dsa_8021q_setup
and modify the existing call sites as appropriate. Note that one call
path, sja1105_best_effort_vlan_filtering_set -> sja1105_vlan_filtering
-> sja1105_setup_8021q_tagging, was already holding this lock.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Most DSA switch tags shift the EtherType to the right, causing the
master to not parse the VLAN as VLAN.
However, not all switches do that (example: tail tags, tag_8021q etc),
and if the DSA master has "rx-vlan-filter: on" in ethtool -k, then we
have a problem.

Therefore, we could populate the VLAN table of the master, just in case
(for some switches it will not make a difference), so that network I/O
can work even with a VLAN filtering master.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When the bridge has VLAN awareness disabled there isn't any duplication
of functionality, since the bridge does not process VLAN. Don't deny
adding 8021q uppers to DSA switch ports in that case. The switch is
supposed to simply pass traffic leaving the VLAN tag as-is, and the
stack will happily strip the VLAN tag for all 8021q uppers that exist.

We need to ensure that there are no 8021q uppers when the user attempts
to enable bridge vlan_filtering.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The current logic beats me a little bit. The comment that "bridge skips
-EOPNOTSUPP, so skip the prepare phase" was introduced in commit
fb2dabad ("net: dsa: support VLAN filtering switchdev attr").

I'm not sure:
(a) ok, the bridge skips -EOPNOTSUPP, but, so what, where are we
    returning -EOPNOTSUPP?
(b) even if we are, and I'm just not seeing it, what is the causality
    relationship between the bridge skipping -EOPNOTSUPP and DSA
    skipping the prepare phase, and just returning zero?

One thing is certain beyond doubt though, and that is that DSA currently
refuses VLAN filtering from the "commit" phase instead of "prepare", and
that this is not a good thing:

ip link add br0 type bridge
ip link add br1 type bridge vlan_filtering 1
ip link set swp2 master br0
ip link set swp3 master br1
[ 3790.379389] 001: sja1105 spi0.1: VLAN filtering is a global setting
[ 3790.379399] 001: ------------[ cut here ]------------
[ 3790.379403] 001: WARNING: CPU: 1 PID: 515 at net/switchdev/switchdev.c:157 switchdev_port_attr_set_now+0x9c/0xa4
[ 3790.379420] 001: swp3: Commit of attribute (id=6) failed.
[ 3790.379533] 001: [<c11ff588>] (switchdev_port_attr_set_now) from [<c11b62e4>] (nbp_vlan_init+0x84/0x148)
[ 3790.379544] 001: [<c11b62e4>] (nbp_vlan_init) from [<c11a2ff0>] (br_add_if+0x514/0x670)
[ 3790.379554] 001: [<c11a2ff0>] (br_add_if) from [<c1031b5c>] (do_setlink+0x38c/0xab0)
[ 3790.379565] 001: [<c1031b5c>] (do_setlink) from [<c1036fe8>] (__rtnl_newlink+0x44c/0x748)
[ 3790.379573] 001: [<c1036fe8>] (__rtnl_newlink) from [<c1037328>] (rtnl_newlink+0x44/0x60)
[ 3790.379580] 001: [<c1037328>] (rtnl_newlink) from [<c10315fc>] (rtnetlink_rcv_msg+0x124/0x2f8)
[ 3790.379590] 001: [<c10315fc>] (rtnetlink_rcv_msg) from [<c10926b8>] (netlink_rcv_skb+0xb8/0x110)
[ 3790.379806] 001: ---[ end trace 0000000000000002 ]---
[ 3790.379819] 001: sja1105 spi0.1 swp3: failed to initialize vlan filtering on this port

So move the current logic that may fail (except ds->ops->port_vlan_filtering,
that is way harder) into the prepare stage of the switchdev transaction.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is checking for the following order of operations, and makes sure
to deny that configuration:

ip link add link swp2 name swp2.100 type vlan id 100
ip link add br0 type bridge vlan_filtering 1
ip link set swp2 master br0
bridge vlan add dev swp2 vid 100

Instead of using vlan_for_each(), which looks at the VLAN filters
installed with vlan_vid_add(), just track the 8021q uppers. This has the
advantage of freeing up the vlan_vid_add() call for actual VLAN
filtering.

There is another change in this patch. The check is moved in slave.c,
from switch.c. I don't think it makes sense to have this 8021q upper
check for each switch port that gets notified of that VLAN addition
(these include DSA links and CPU ports, we know those can't have 8021q
uppers because they don't have a net_device registered for them), so
just do it in slave.c, for that one slave interface.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

DSA tries to prevent having a VLAN added by a bridge and by an 802.1Q
upper at the same time. It does that by checking the VID in
.ndo_vlan_rx_add_vid(), since that's something that the 8021q module
calls, via vlan_vid_add(). When a VLAN matches in both subsystems, this
check returns -EBUSY.

However the vlan_vid_add() function isn't specific to the 8021q module
in any way at all. It is simply the kernel's way to tell an interface to
add a VLAN to its RX filter and not drop that VLAN. So there's no reason
to return -EBUSY when somebody tries to call vlan_vid_add() for a VLAN
that was installed by the bridge. The proper behavior is to accept that
configuration.

So what's wrong is how DSA checks that it has an 8021q upper. It should
look at the actual uppers for that, not just assume that the 8021q
module was somewhere in the call stack of .ndo_vlan_rx_add_vid().
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We'll be adding a new check in the PRECHANGEUPPER notifier, where we'll
need to check some VLAN uppers. It is hard to do that when there is
already a function named dsa_slave_upper_vlan_check. So rename this one.

Not to mention that this function probably shouldn't have started with
"dsa_slave_" in the first place, since the struct net_device argument
isn't a DSA slave, but an 8021q upper of one.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>