Sparse reports a warning at netlink_seq_start()

warning: context imbalance in netlink_seq_start() - wrong count at exit
The root cause is the missing annotation at netlink_seq_start()
Add the missing  __acquires(RCU) annotation
Signed-off-by: NJules Irenge <jbi.octave@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Sparse reports warning at tcp_child_process()
warning: context imbalance in tcp_child_process() - unexpected unlock
The root cause is the missing annotation at tcp_child_process()

Add the missing __releases(&((child)->sk_lock.slock)) annotation
Signed-off-by: NJules Irenge <jbi.octave@gmail.com>
Reviewed-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Sparse reports warnings at raw_seq_start() and raw_seq_stop()

warning: context imbalance in raw_seq_start() - wrong count at exit
warning: context imbalance in raw_seq_stop() - unexpected unlock

The root cause is the missing annotations at raw_seq_start()
	and raw_seq_stop()
Add the missing __acquires(&h->lock) annotation
Add the missing __releases(&h->lock) annotation
Signed-off-by: NJules Irenge <jbi.octave@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In their .attach callback, mq[prio] only add the qdiscs of the currently
active TX queues to the device's qdisc hash list.
If a user later increases the number of active TX queues, their qdiscs
are not visible via eg. 'tc qdisc show'.

Add a hook to netif_set_real_num_tx_queues() that walks all active
TX queues and adds those which are missing to the hash list.

CC: Eric Dumazet <edumazet@google.com>
CC: Jamal Hadi Salim <jhs@mojatatu.com>
CC: Cong Wang <xiyou.wangcong@gmail.com>
CC: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When pktgen is used to measure the performance of dev_queue_xmit()
packet handling in the core, it is preferable to not hand down
packets to a low-level Ethernet driver as it would distort the
measurements.

Allow using pktgen on the loopback device, thus constraining
measurements to core code.
Signed-off-by: NLukas Wunner <lukas@wunner.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The mptcp rcvbuf size is adjusted according to the subflow rcvbuf size.
This should not be done if userspace did set a fixed value.

Fixes: 600911ff ("mptcp: add rmem queue accounting")
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 105e808c ("pie: remove pie_vars->accu_prob_overflows")
changes the scale of probability values in PIE from (2^64 - 1) to
(2^56 - 1). This affects the precision of tc_pie_xstats->prob in
user space.

This patch ensures user space is unaffected.
Suggested-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NLeslie Monis <lesliemonis@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add TCP_NLA_BYTES_NOTSENT to SCM_TIMESTAMPING_OPT_STATS that reports
bytes in the write queue but not sent. This is the same metric as
what is exported with tcp_info.tcpi_notsent_bytes.
Signed-off-by: NYousuk Seung <ysseung@google.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NSoheil Hassas Yeganeh <soheil@google.com>
Acked-by: NYuchung Cheng <ycheng@google.com>
Acked-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Convert zones_lock spinlock to zones_mutex mutex,
and struct (tcf_ct_flow_table)->ref to a refcount,
so that control path can use regular GFP_KERNEL allocations
from standard process context. This is more robust
in case of memory pressure.

The refcount is needed because tcf_ct_flow_table_put() can
be called from RCU callback, thus in BH context.

The issue was spotted by syzbot, as rhashtable_init()
was called with a spinlock held, which is bad since GFP_KERNEL
allocations can sleep.

Note to developers : Please make sure your patches are tested
with CONFIG_DEBUG_ATOMIC_SLEEP=y

BUG: sleeping function called from invalid context at mm/slab.h:565
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 9582, name: syz-executor610
2 locks held by syz-executor610/9582:
 #0: ffffffff8a34eb80 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8a34eb80 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x3f9/0xad0 net/core/rtnetlink.c:5437
 #1: ffffffff8a3961b8 (zones_lock){+...}, at: spin_lock_bh include/linux/spinlock.h:343 [inline]
 #1: ffffffff8a3961b8 (zones_lock){+...}, at: tcf_ct_flow_table_get+0xa3/0x1700 net/sched/act_ct.c:67
Preemption disabled at:
[<0000000000000000>] 0x0
CPU: 0 PID: 9582 Comm: syz-executor610 Not tainted 5.6.0-rc3-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+0x188/0x20d lib/dump_stack.c:118
 ___might_sleep.cold+0x1f4/0x23d kernel/sched/core.c:6798
 slab_pre_alloc_hook mm/slab.h:565 [inline]
 slab_alloc_node mm/slab.c:3227 [inline]
 kmem_cache_alloc_node_trace+0x272/0x790 mm/slab.c:3593
 __do_kmalloc_node mm/slab.c:3615 [inline]
 __kmalloc_node+0x38/0x60 mm/slab.c:3623
 kmalloc_node include/linux/slab.h:578 [inline]
 kvmalloc_node+0x61/0xf0 mm/util.c:574
 kvmalloc include/linux/mm.h:645 [inline]
 kvzalloc include/linux/mm.h:653 [inline]
 bucket_table_alloc+0x8b/0x480 lib/rhashtable.c:175
 rhashtable_init+0x3d2/0x750 lib/rhashtable.c:1054
 nf_flow_table_init+0x16d/0x310 net/netfilter/nf_flow_table_core.c:498
 tcf_ct_flow_table_get+0xe33/0x1700 net/sched/act_ct.c:82
 tcf_ct_init+0xba4/0x18a6 net/sched/act_ct.c:1050
 tcf_action_init_1+0x697/0xa20 net/sched/act_api.c:945
 tcf_action_init+0x1e9/0x2f0 net/sched/act_api.c:1001
 tcf_action_add+0xdb/0x370 net/sched/act_api.c:1411
 tc_ctl_action+0x366/0x456 net/sched/act_api.c:1466
 rtnetlink_rcv_msg+0x44e/0xad0 net/core/rtnetlink.c:5440
 netlink_rcv_skb+0x15a/0x410 net/netlink/af_netlink.c:2478
 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline]
 netlink_unicast+0x537/0x740 net/netlink/af_netlink.c:1329
 netlink_sendmsg+0x882/0xe10 net/netlink/af_netlink.c:1918
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:672
 ____sys_sendmsg+0x6b9/0x7d0 net/socket.c:2343
 ___sys_sendmsg+0x100/0x170 net/socket.c:2397
 __sys_sendmsg+0xec/0x1b0 net/socket.c:2430
 do_syscall_64+0xf6/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4403d9
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffd719af218 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004403d9
RDX: 0000000000000000 RSI: 0000000020000300 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 0000000000000005 R09: 00000000004002c8
R10: 0000000000000008 R11: 00000000000

Fixes: c34b961a ("net/sched: act_ct: Create nf flow table per zone")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Paul Blakey <paulb@mellanox.com>
Cc: Jiri Pirko <jiri@mellanox.com>
Reported-by: Nsyzbot <syzkaller@googlegroups.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently, user who is adding an action expects HW to report stats,
however it does not have exact expectations about the stats types.
That is aligned with TCA_ACT_HW_STATS_TYPE_ANY.

Allow user to specify the type of HW stats for an action and require it.

Pass the information down to flow_offload layer.
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Introduce flow_action_basic_hw_stats_types_check() helper and use it
in drivers. That sanitizes the drivers which do not have support
for action HW stats types.
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Invoke ndo_setup_tc() as appropriate to signal init / replacement,
destroying and dumping of pFIFO / bFIFO Qdisc.

A lot of the FIFO logic is used for pFIFO_head_drop as well, but that's a
semantically very different Qdisc that isn't really in the same boat as
pFIFO / bFIFO. Split some of the functions to keep the Qdisc intact.
Signed-off-by: NPetr Machata <petrm@mellanox.com>
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Linux supports 22 different interrupt coalescing parameters.
No driver implements them all. Some drivers just ignore the
ones they don't support, while others have to carry a long
list of checks to reject unsupported settings.

To simplify the drivers add the ability to specify inside
ethtool_ops which parameters are supported and let the core
reject attempts to set any other one.

This commit makes the mechanism an opt-in, only drivers which
set ethtool_opts->coalesce_types to a non-zero value will have
the checks enforced.

The same mask is used for global and per queue settings.

v3: - move the (temporary) check if driver defines types
      earlier (Michal)
    - rename used_types -> nonzero_params, and
      coalesce_types -> supported_coalesce_params (Alex)
    - use EOPNOTSUPP instead of EINVAL (Andrew, Michal)

Leaving the long series of ifs for now, it seems nice to
be able to grep for the field and flag names. This will
probably have to be revisited once netlink support lands.
Signed-off-by: NJakub Kicinski <kuba@kernel.org>
Reviewed-by: NJacob Keller <jacob.e.keller@intel.com>
Reviewed-by: NMichal Kubecek <mkubecek@suse.cz>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: NAlexander Duyck <alexander.h.duyck@linux.intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the commit e0a4b997 ("hsr: use upper/lower device infrastructure"),
dev_get() was removed but dev_put() in the error path wasn't removed.
So, if creating hsr interface command is failed, the reference counter leak
of lower interface would occur.

Test commands:
    ip link add dummy0 type dummy
    ip link add ipvlan0 link dummy0 type ipvlan mode l2
    ip link add ipvlan1 link dummy0 type ipvlan mode l2
    ip link add hsr0 type hsr slave1 ipvlan0 slave2 ipvlan1
    ip link del ipvlan0

Result:
[  633.271992][ T1280] unregister_netdevice: waiting for ipvlan0 to become free. Usage count = -1

Fixes: e0a4b997 ("hsr: use upper/lower device infrastructure")
Signed-off-by: NTaehee Yoo <ap420073@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Ocelot has the concept of a CPU port. The CPU port is represented in the
forwarding and the queueing system, but it is not a physical device. The
CPU port can either be accessed via register-based injection/extraction
(which is the case of Ocelot), via Frame-DMA (similar to the first one),
or "connected" to a physical Ethernet port (called NPI in the datasheet)
which is the case of the Felix DSA switch.

In Ocelot the CPU port is at index 11.
In Felix the CPU port is at index 6.

The CPU bit is treated special in the forwarding, as it is never cleared
from the forwarding port mask (once added to it). Other than that, it is
treated the same as a normal front port.

Both Felix and Ocelot should use the CPU port in the same way. This
means that Felix should not use the NPI port directly when forwarding to
the CPU, but instead use the CPU port.

This patch is fixing this such that Felix will use port 6 as its CPU
port, and just use the NPI port to carry the traffic.

Therefore, eliminate the "ocelot->cpu" variable which was holding the
index of the NPI port for Felix, and the index of the CPU port module
for Ocelot, so the variable was actually configuring different things
for different drivers and causing at least part of the confusion.

Also remove the "ocelot->num_cpu_ports" variable, which is the result of
another confusion. The 2 CPU ports mentioned in the datasheet are
because there are two frame extraction channels (register based or DMA
based). This is of no relevance to the driver at the moment, and
invisible to the analyzer module.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Suggested-by: NAllan W. Nielsen <allan.nielsen@microchip.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The variable pie_vars->accu_prob is used as an accumulator for
probability values. Since probabilty values are scaled using the
MAX_PROB macro denoting (2^64 - 1), pie_vars->accu_prob is
likely to overflow as it is of type u64.

The variable pie_vars->accu_prob_overflows counts the number of
times the variable pie_vars->accu_prob overflows.

The MAX_PROB macro needs to be equal to at least (2^39 - 1) in
order to do precise calculations without any underflow. Thus
MAX_PROB can be reduced to (2^56 - 1) without affecting the
precision in calculations drastically. Doing so will eliminate
the need for the variable pie_vars->accu_prob_overflows as the
variable pie_vars->accu_prob will never overflow.

Removing the variable pie_vars->accu_prob_overflows also reduces
the size of the structure pie_vars to exactly 64 bytes.
Signed-off-by: NMohit P. Tahiliani <tahiliani@nitk.edu.in>
Signed-off-by: NGautam Ramakrishnan <gautamramk@gmail.com>
Signed-off-by: NLeslie Monis <lesliemonis@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In function pie_calculate_probability(), the variables alpha and
beta are of type u64. The variables qdelay, qdelay_old and
params->target are of type psched_time_t (which is also u64).
The explicit type casting done when calculating the value for
the variable delta is redundant and not required.
Signed-off-by: NMohit P. Tahiliani <tahiliani@nitk.edu.in>
Signed-off-by: NGautam Ramakrishnan <gautamramk@gmail.com>
Signed-off-by: NLeslie Monis <lesliemonis@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove ambiguity by using the term backlog instead of qlen when
representing the queue length in bytes.
Signed-off-by: NMohit P. Tahiliani <tahiliani@nitk.edu.in>
Signed-off-by: NGautam Ramakrishnan <gautamramk@gmail.com>
Signed-off-by: NLeslie Monis <lesliemonis@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

To make the filler functions more generic, use network
relative skb pulling.
Signed-off-by: NPaul Blakey <paulb@mellanox.com>
Acked-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Reviewed-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When checking the protocol number tcf_ct_flow_table_lookup() handles
the flow as if it's always ipv4, while it can be ipv6.

Instead, refactor the code to fetch the tcp header, if available,
in the relevant family (ipv4/ipv6) filler function, and do the
check on the returned tcp header.

Fixes: 46475bb2 ("net/sched: act_ct: Software offload of established flows")
Signed-off-by: NPaul Blakey <paulb@mellanox.com>
Acked-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Reviewed-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Due to the immense variety of classification keys and actions available
for tc-flower, as well as due to potentially very different DSA switch
capabilities, it doesn't make a lot of sense for the DSA mid layer to
even attempt to interpret these. So just pass them on to the underlying
switch driver.

DSA implements just the standard boilerplate for binding and unbinding
flow blocks to ports, since nobody wants to deal with that.
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 2 second delay before calling qrtr_ns_init() meant that the remote
processors would register as endpoints in qrtr and the say_hello() call
would therefor broadcast the outgoing HELLO to them. With the HELLO
handshake corrected this delay is no longer needed.
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Tested-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Lost in the translation from the user space implementation was the
detail that HELLO mesages must be exchanged between each node pair.  As
such the incoming HELLO must be replied to.

Similar to the previous implementation no effort is made to prevent two
Linux boxes from continuously sending HELLO messages back and forth,
this is left to a follow up patch.

say_hello() is moved, to facilitate the new call site.

Fixes: 0c2204a4 ("net: qrtr: Migrate nameservice to kernel from userspace")
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Tested-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a DATA_FIN is sent in a MPTCP DSS option that contains a data
mapping, the DATA_FIN consumes one byte of space in the mapping. In this
case, the DATA_FIN should only be included in the DSS option if its
sequence number aligns with the end of the mapped data. Otherwise the
subflow can send an incorrect implicit sequence number for the DATA_FIN,
and the DATA_ACK for that sequence number would not close the
MPTCP-level connection correctly.
Signed-off-by: NMat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Instead of reading the MPTCP-level sequence number when sending DATA_FIN,
store the data in the subflow so it can be safely accessed when the
subflow TCP headers are written to the packet without the MPTCP-level
lock held. This also allows the MPTCP-level socket to close individual
subflows without closing the MPTCP connection.
Signed-off-by: NMat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

MPTCP should wait for an active connection or skip sending depending on
the connection state, as TCP does. This happens before the possible
passthrough to a regular TCP sendmsg because the subflow's socket type
(MPTCP or TCP fallback) is not known until the connection is
complete. This is also relevent at disconnect time, where data should
not be sent in certain MPTCP-level connection states.
Signed-off-by: NMat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently mlx5 PCI PF and VF devlink devices register their ports as
physical port in non-representors mode.

Introduce a new port flavour as virtual so that virtual devices can
register 'virtual' flavour to make it more clear to users.

An example of one PCI PF and 2 PCI virtual functions, each having
one devlink port.

$ devlink port show
pci/0000:06:00.0/1: type eth netdev ens2f0 flavour physical port 0
pci/0000:06:00.2/1: type eth netdev ens2f2 flavour virtual port 0
pci/0000:06:00.3/1: type eth netdev ens2f3 flavour virtual port 0
Reviewed-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NParav Pandit <parav@mellanox.com>
Acked-by: NJakub Kicinski <kuba@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Offload nf conntrack processing by looking up the 5-tuple in the
zone's flow table.

The nf conntrack module will process the packets until a connection is
in established state. Once in established state, the ct state pointer
(nf_conn) will be restored on the skb from a successful ft lookup.
Signed-off-by: NPaul Blakey <paulb@mellanox.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a ft entry when connections enter an established state and delete
the connections when they leave the established state.

The flow table assumes ownership of the connection. In the following
patch act_ct will lookup the ct state from the FT. In future patches,
drivers will register for callbacks for ft add/del events and will be
able to use the information to offload the connections.

Note that connection aging is managed by the FT.
Signed-off-by: NPaul Blakey <paulb@mellanox.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use the NF flow tables infrastructure for CT offload.

Create a nf flow table per zone.

Next patches will add FT entries to this table, and do
the software offload.
Signed-off-by: NPaul Blakey <paulb@mellanox.com>
Reviewed-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The data pointers of ipv6 sysctl are set one by one which is hard to
maintain, especially with kconfig. This patch simplifies it by using
math to point the per net sysctls into the appropriate struct net,
just like what we did for ipv4.
Signed-off-by: NCambda Zhu <cambda@linux.alibaba.com>
Reviewed-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Three virtual devices (ibmveth, virtio_net, and netvsc) all have
similar code to set link settings and validate ethtool command. To
eliminate duplication of code, it is factored out into core/ethtool.c.
Signed-off-by: NCris Forno <cforno12@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

netdev_upper_dev_link() is useful to manage lower/upper interfaces.
And this function internally validates looping, maximum depth.
All or most virtual interfaces that could have a real interface
(e.g. macsec, macvlan, ipvlan etc.) use lower/upper infrastructure.
Signed-off-by: NTaehee Yoo <ap420073@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In order to access the port list, the hsr_port_get_hsr() is used.
And this is protected by RTNL and RCU.
The hsr_fill_info(), hsr_check_carrier(), hsr_dev_open() and
hsr_get_max_mtu() are protected by RTNL.
So, rcu_read_lock() in these functions are not necessary.
The hsr_handle_frame() also uses rcu_read_lock() but this function
is called by packet path.
It's already protected by RCU.
So, the rcu_read_lock() in hsr_handle_frame() can be removed.
Signed-off-by: NTaehee Yoo <ap420073@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When HSR interface is sending a frame, it finds a node with
the destination ethernet address from the list.
If there is no node, it calls WARN_ONCE().
But, using WARN_ONCE() for this situation is a little bit overdoing.
So, in this patch, the netdev_err() is used instead.
Signed-off-by: NTaehee Yoo <ap420073@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If HSR uses the extack instead of netdev_info(), users can get
error messages immediately without any checking the kernel message.
Signed-off-by: NTaehee Yoo <ap420073@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If it uses debugfs_remove_recursive() instead of debugfs_remove(),
hsr_priv() doesn't need to have "node_tbl_file" pointer variable.
Signed-off-by: NTaehee Yoo <ap420073@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: NGustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The only users for such argument are the UDP protocol and the UNIX
socket family. We can safely reclaim the accounted memory directly
from the UDP code and, after the previous patch, we can do scm
stats accounting outside the datagram helpers.

Overall this cleans up a bit some datagram-related helpers, and
avoids an indirect call per packet in the UDP receive path.

v1 -> v2:
 - call scm_stat_del() only when not peeking - Kirill
 - fix build issue with CONFIG_INET_ESPINTCP
Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
Reviewed-by: NKirill Tkhai <ktkhai@virtuozzo.com>
Reviewed-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

So the scm_stat_{add,del} helper can be invoked with no
additional lock held.

This clean-up the code a bit and will make the next
patch easier.
Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
Reviewed-by: NKirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>