{un,}register_netdevice_notifier() iterate over all net namespaces
hashed to net_namespace_list. But pernet_operations register and
unregister netdevices in unhashed net namespace, and they are not
seen for netdevice notifiers. This results in asymmetry:

1)Race with register_netdevice_notifier()
  pernet_operations::init(net)	...
   register_netdevice()		...
    call_netdevice_notifiers()  ...
      ... nb is not called ...
  ...				register_netdevice_notifier(nb) -> net skipped
  ...				...
  list_add_tail(&net->list, ..) ...

  Then, userspace stops using net, and it's destructed:

  pernet_operations::exit(net)
   unregister_netdevice()
    call_netdevice_notifiers()
      ... nb is called ...

This always happens with net::loopback_dev, but it may be not the only device.

2)Race with unregister_netdevice_notifier()
  pernet_operations::init(net)
   register_netdevice()
    call_netdevice_notifiers()
      ... nb is called ...

  Then, userspace stops using net, and it's destructed:

  list_del_rcu(&net->list)	...
  pernet_operations::exit(net)  unregister_netdevice_notifier(nb) -> net skipped
   dev_change_net_namespace()	...
    call_netdevice_notifiers()
      ... nb is not called ...
   unregister_netdevice()
    call_netdevice_notifiers()
      ... nb is not called ...

This race is more danger, since dev_change_net_namespace() moves real
network devices, which use not trivial netdevice notifiers, and if this
will happen, the system will be left in unpredictable state.

The patch closes the race. During the testing I found two places,
where register_netdevice_notifier() is called from pernet init/exit
methods (which led to deadlock) and fixed them (see previous patches).

The review moved me to one more unusual registration place:
raw_init() (can driver). It may be a reason of problems,
if someone creates in-kernel CAN_RAW sockets, since they
will be destroyed in exit method and raw_release()
will call unregister_netdevice_notifier(). But grep over
kernel tree does not show, someone creates such sockets
from kernel space.

Theoretically, there can be more places like this, and which are
hidden from review, but we found them on the first bumping there
(since there is no a race, it will be 100% reproducible).
Signed-off-by: NKirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Register netdevice notifier for every iptable entry
is not good, since this breaks modularity, and
the hidden synchronization is based on rtnl_lock().

This patch reworks the synchronization via new lock,
while the rest of logic remains as it was before.
This is required for the next patch.

Tested via:

while :; do
	unshare -n iptables -t mangle -A OUTPUT -j TEE --gateway 1.1.1.2 --oif lo;
done
Signed-off-by: NKirill Tkhai <ktkhai@virtuozzo.com>
Acked-by: NPablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently, driver registers it from pernet_operations::init method,
and this breaks modularity, because initialization of net namespace
and netdevice notifiers are orthogonal actions. We don't have
per-namespace netdevice notifiers; all of them are global for all
devices in all namespaces.
Signed-off-by: NKirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Mike Looijmans says:

====================
of_net: Implement of_get_nvmem_mac_address helper

Posted this as a small set now, with an (optional) second patch that shows
how the changes work and what I've used to test the code on a Topic Miami board.
I've taken the liberty to add appropriate "Acked" and "Review" tags.

v4: Replaced "6" with ETH_ALEN

v3: Add patch that implements mac in nvmem for the Cadence MACB controller
    Remove the integrated of_get_mac_address call

v2: Use of_nvmem_cell_get to avoid needing the assiciated device
    Use void* instead of char*
    Add devicetree binding doc
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Call of_get_nvmem_mac_address() to fetch the MAC address from an nvmem
cell, if one is provided in the device tree. This allows the address to
be stored in an I2C EEPROM device for example.
Signed-off-by: NMike Looijmans <mike.looijmans@topic.nl>
Acked-by: NNicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It's common practice to store MAC addresses for network interfaces into
nvmem devices. However the code to actually do this in the kernel lacks,
so this patch adds of_get_nvmem_mac_address() for drivers to obtain the
address from an nvmem cell provider.

This is particulary useful on devices where the ethernet interface cannot
be configured by the bootloader, for example because it's in an FPGA.
Signed-off-by: NMike Looijmans <mike.looijmans@topic.nl>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Jakub Kicinski says:

====================
nfp: flower: handle MTU changes

This set improves MTU handling for flower offload.  The max MTU is
correctly capped and physical port MTU is communicated to the FW
(and indirectly HW).
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Trigger a port mod message to request an MTU change on the NIC when any
physical port representor is assigned a new MTU value. The driver waits
10 msec for an ack that the FW has set the MTU. If no ack is received the
request is rejected and an appropriate warning flagged.

Rather than maintain an MTU queue per repr, one is maintained per app.
Because the MTU ndo is protected by the rtnl lock, there can never be
contention here. Portmod messages from the NIC are also protected by
rtnl so we first check if the portmod is an ack and, if so, handle outside
rtnl and the cmsg work queue.

Acks are detected by the marking of a bit in a portmod response. They are
then verfied by checking the port number and MTU value expected by the
app. If the expected MTU is 0 then no acks are currently expected.

Also, ensure that the packet headroom reserved by the flower firmware is
considered when accepting an MTU change on any repr.
Signed-off-by: NJohn Hurley <john.hurley@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Rename the 'change_mtu' app callback to 'check_mtu'. This is called
whenever an MTU change is requested on a netdev. It can reject the
change but is not responsible for implementing it.

Introduce a new 'repr_change_mtu' app callback that is hit when the MTU
of a repr is to be changed. This is responsible for performing the MTU
change and verifying it.
Signed-off-by: NJohn Hurley <john.hurley@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Florian Fainelli says:

====================
phylink: API changes

This patch series contains two API changes to PHYLINK which will later be used
by DSA to migrate to PHYLINK. Because these are API changes that impact other
outstanding work (e.g: MVPP2) I would rather get them included sooner to minimize
conflicts.

Thank you!

Changes in v2:

- added missing documentation to mac_link_{up,down} that the interface
  must be configured in mac_config()

- added Russell's, Andrew's and my tags
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Provide a pointer to the SFP bus in struct net_device, so that the
ethtool module EEPROM methods can access the SFP directly, rather
than needing every user to provide a hook for it.
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NRussell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NRussell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In preparation for having DSA transition entirely to PHYLINK, we need to pass a
PHY interface type to the mac_link_{up,down} callbacks because we may have to
make decisions on that (e.g: turn on/off RGMII interfaces etc.). We do not pass
an entire phylink_link_state because not all parameters (pause, duplex etc.) are
defined when the link is down, only link and interface are.

Update mvneta accordingly since it currently implements phylink_mac_ops.
Acked-by: NRussell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Acked-by: NRussell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Shrikrishna Khare would no longer maintain the vmxnet3 driver. Taking
over the role of vmxnet3 maintainer.
Signed-off-by: NRonak Doshi <doshir@vmware.com>
Signed-off-by: NShrikrishna Khare <skhare@vmware.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Florian Fainelli says:

====================
net: Broadcom drivers coalescing fixes

Following Tal's review of the adaptive RX/TX coalescing feature added to the
SYSTEMPORT and GENET driver a number of things showed up:

- adaptive TX coalescing is not actually a good idea with the current way
  the estimator will program the ring, this results in a higher CPU load, NAPI
  on TX already does a reasonably good job at maintaining the interrupt count low

- both SYSTEMPORT and GENET would suffer from the same issues while configuring
  coalescing parameters where the values would just not be applied correctly
  based on user settings, so we fix that too

Tal, thanks again for your feedback, I would appreciate if you could review that
the new behavior appears to be implemented correctly.

Thanks!

Changes in v2:

- added Tal's reviewed-by to the first patch
- split DIM initialization from coalescing parameters initialization
- avoid duplicating the same code in bcmgenet_set_coalesce() when configuring RX rings
- fixed the condition where default DIM parameters would be applied when
  adaptive RX coalescing would be enabled, do this only if it was disabled before
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There were a number of issues with setting the RX coalescing parameters:

- we would not be preserving values that would have been configured
  across close/open calls, instead we would always reset to no timeout
  and 1 interrupt per packet, this would also prevent DIM from setting its
  default usec/pkts values

- when adaptive RX would be turned on, we woud not be fetching the
  default parameters, we would stay with no timeout/1 packet per interrupt
  until the estimator kicks in and changes that

- finally disabling adaptive RX coalescing while providing parameters
  would not be honored, and we would stay with whatever DIM had previously
  determined instead of the user requested parameters

Fixes: 9f4ca058 ("net: bcmgenet: Add support for adaptive RX coalescing")
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NTal Gilboa <talgi@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There were a number of issues with setting the RX coalescing parameters:

- we would not be preserving values that would have been configured
  across close/open calls, instead we would always reset to no timeout
  and 1 interrupt per packet, this would also prevent DIM from setting its
  default usec/pkts values

- when adaptive RX would be turned on, we woud not be fetching the
  default parameters, we would stay with no timeout/1 packet per
  interrupt until the estimator kicks in and changes that

- finally disabling adaptive RX coalescing while providing parameters
  would not be honored, and we would stay with whatever DIM had
  previously determined instead of the user requested parameters

Fixes: b6e0e875 ("net: systemport: Implement adaptive interrupt coalescing")
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NTal Gilboa <talgi@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Adaptive TX coalescing is not currently giving us any advantages and
ends up making the CPU spin more frequently until TX completion. Deny
and disable adaptive TX coalescing for now and rely on static
configuration, we can always add it back later.
Reviewed-by: NTal Gilboa <talgi@mellanox.com>
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

NETIF_F_HW_VLAN_[CS]TAG_FILTER features require more than just a bit
flip in dev->features in order to keep the driver in a consistent state.
These features notify the driver of each added/removed vlan, but toggling
of vlan-filter does not notify the driver accordingly for each of the
existing vlans.

This patch implements a similar solution to NETIF_F_RX_UDP_TUNNEL_PORT
behavior (which notifies the driver about UDP ports in the same manner
that vids are reported).

Each toggling of the features propagates to the 8021q module, which
iterates over the vlans and call add/kill ndo accordingly.
Signed-off-by: NGal Pressman <galp@mellanox.com>
Reviewed-by: NTariq Toukan <tariqt@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix to return a negative error code from the hash filter init error
handling case instead of 0, as done elsewhere in this function.

Fixes: 5c31254e ("cxgb4: initialize hash-filter configuration")
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Merge tag 'wireless-drivers-next-for-davem-2018-03-29' of git://git.kernel.org/pub/scm/linux/kernel/git/kvalo/wireless-drivers-next

Kalle Valo says:

====================
wireless-drivers-next patches for 4.17

Smaller new features to various drivers but nothing really out of
ordinary.

Major changes:

ath10k

* enable chip temperature measurement for QCA6174/QCA9377

* add firmware memory dump for QCA9984

* enable buffer STA on TDLS link for QCA6174

* support different beacon internals in multiple interface scenario
  for QCA988X/QCA99X0/QCA9984/QCA4019

iwlwifi

* support for new PCI IDs for the 9000 family

* support for a new firmware API version

* support for advanced dwell and Optimized Connectivity Experience
  (OCE) in scanning

btrsi

* fix kconfig dependencies

wil6210

* support multiple virtual interfaces
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Merge tag 'mac80211-next-for-davem-2018-03-29' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next

Johannes Berg says:

====================
We have a fair number of patches, but many of them are from the
first bullet here:
 * EAPoL-over-nl80211 from Denis - this will let us fix
   some long-standing issues with bridging, races with
   encryption and more
 * DFS offload support from the qtnfmac folks
 * regulatory database changes for the new ETSI adaptivity
   requirements
 * various other fixes and small enhancements
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Andrew Lunn says:

====================
Add ATU/VTU statistics

Previous patches have added basic support for Address Translation Unit
and VLAN translation Unit violation interrupts. Add statistics
counters for when these occur, which can be accessed using
ethtool. Downgrade one of the particularly spammy warnings from VTU
violations to debug only, now that we have a counter for it.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

VTU miss violations can happen under normal conditions. Don't spam the
kernel log, downgrade the output to debug level only. The statistics
counter will indicate it is happening, if anybody not debugging is
interested.
Signed-off-by: NAndrew Lunn <andrew@lunn.ch>
Reported-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Count the numbers of various ATU and VTU violation statistics and
return them as part of the ethtool -S statistics.
Signed-off-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The proc file cleanup left a label possibly unused:

net/sctp/protocol.c: In function 'sctp_defaults_init':
net/sctp/protocol.c:1304:1: error: label 'err_init_proc' defined but not used [-Werror=unused-label]

This adds an #ifdef around it to match the respective 'goto'.

Fixes: d47d08c8 ("sctp: use proc_remove_subtree()")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use the module_pci_driver() macro to make the code simpler
by eliminating module_init and module_exit calls.
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fixes the following sparse warning:

drivers/net/ethernet/broadcom/genet/bcmgenet.c:1351:16: warning:
 Using plain integer as NULL pointer
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Acked-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The skb_segment() function returns error pointers on error.  It never
returns NULL.

Fixes: 76db8087 ("net: bpf: add a test for skb_segment in test_bpf module")
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Reviewed-by: NYonghong Song <yhs@fb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Cotsworks modules fail the checksums - it appears that Cotsworks
reprograms the EEPROM at the end of production with the final product
information (serial, date code, and exact part number for module
options) and fails to update the checksum.

Work around this by detecting the Cotsworks name in the manufacturer
field, and reducing the checksum failures to warnings rather than a
hard error.
Signed-off-by: NRussell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Sudarsana Reddy Kalluru says:

====================
qed*: Flash upgrade support.

The patch series adds adapter flash upgrade support for qed/qede drivers.

Please consider applying it to net-next branch.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The patch adds ethtool callback implementation for flash update.
Signed-off-by: NSudarsana Reddy Kalluru <Sudarsana.Kalluru@cavium.com>
Signed-off-by: NAriel Elior <ariel.elior@cavium.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds the required driver support for updating the flash or
non volatile memory of the adapter. At highlevel, flash upgrade comprises
of reading the flash images from the input file, validating the images and
writing them to the respective paritions.
Signed-off-by: NSudarsana Reddy Kalluru <Sudarsana.Kalluru@cavium.com>
Signed-off-by: NAriel Elior <ariel.elior@cavium.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds APIs for flash access.
Signed-off-by: NSudarsana Reddy Kalluru <Sudarsana.Kalluru@cavium.com>
Signed-off-by: NAriel Elior <ariel.elior@cavium.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NSudarsana Reddy Kalluru <Sudarsana.Kalluru@cavium.com>
Signed-off-by: NAriel Elior <ariel.elior@cavium.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds support for populating the flash image attributes.
Signed-off-by: NSudarsana Reddy Kalluru <Sudarsana.Kalluru@cavium.com>
Signed-off-by: NAriel Elior <ariel.elior@cavium.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This FW contains several fixes and features

RDMA Features
- SRQ support
- XRC support
- Memory window support
- RDMA low latency queue support
- RDMA bonding support

RDMA bug fixes
- RDMA remote invalidate during retransmit fix
- iWARP MPA connect interop issue with RTR fix
- iWARP Legacy DPM support
- Fix MPA reject flow
- iWARP error handling
- RQ WQE validation checks

MISC
- Fix some HSI types endianity
- New Restriction: vlan insertion in core_tx_bd_data can't be set
  for LB packets

ETH
- HW QoS offload support
- Fix vlan, dcb and sriov flow of VF sending a packet with
  inband VLAN tag instead of default VLAN
- Allow GRE version 1 offloads in RX flow
- Allow VXLAN steering

iSCSI / FcoE
- Fix bd availability checking flow
- Support 256th sge proerly in iscsi/fcoe retransmit
- Performance improvement
- Fix handle iSCSI command arrival with AHS and with immediate
- Fix ipv6 traffic class configuration

DEBUG
- Update debug utilities
Signed-off-by: NMichal Kalderon <Michal.Kalderon@cavium.com>
Signed-off-by: NTomer Tayar <Tomer.Tayar@cavium.com>
Signed-off-by: NManish Rangankar <Manish.Rangankar@cavium.com>
Signed-off-by: NAriel Elior <Ariel.Elior@cavium.com>
Acked-by: NJason Gunthorpe <jgg@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

IPv4 was changed in commit 52a773d6 ("net: Export ip fragment
sysctl to unprivileged users")

The only sysctl that is not per-netns is not used :
ip6frag_secret_interval
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

During heavy tx traffic, control messages (sent by liquidio driver to NIC
firmware) sometimes do not get processed in a timely manner.  Reason is:
the low-level metadata of control messages and that of egress network
packets indicate that they have the same priority.

Fix it by setting a higher priority for control messages through the new
ctrl_qpg field in the oct_txpciq struct.  It is the NIC firmware that does
the actual setting of priority by writing to the new ctrl_qpg field; the
host driver treats that value as opaque and just assigns it to pki_ih3->qpg
Signed-off-by: NIntiyaz Basha <intiyaz.basha@cavium.com>
Signed-off-by: NFelix Manlunas <felix.manlunas@cavium.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

David Ahern says:

====================
net: Allow FIB notifiers to fail add and replace

I wanted to revisit how resource overload is handled for hardware offload
of FIB entries and rules. At the moment, the in-kernel fib notifier can
tell a driver about a route or rule add, replace, and delete, but the
notifier can not affect the action. Specifically, in the case of mlxsw
if a route or rule add is going to overflow the ASIC resources the only
recourse is to abort hardware offload. Aborting offload is akin to taking
down the switch as the path from data plane to the control plane simply
can not support the traffic bandwidth of the front panel ports. Further,
the current state of FIB notifiers is inconsistent with other resources
where a driver can affect a user request - e.g., enslavement of a port
into a bridge or a VRF.

As a result of the work done over the past 3+ years, I believe we are
at a point where we can bring consistency to the stack and offloads,
and reliably allow the FIB notifiers to fail a request, pushing an error
along with a suitable error message back to the user. Rather than
aborting offload when the switch is out of resources, userspace is simply
prevented from adding more routes and has a clear indication of why.

This set does not resolve the corner case where rules or routes not
supported by the device are installed prior to the driver getting loaded
and registering for FIB notifications. In that case, hardware offload has
not been established and it can refuse to offload anything, sending
errors back to userspace via extack. Since conceptually the driver owns
the netdevices associated with its asic, this corner case mainly applies
to unsupported rules and any races during the bringup phase.

Patch 1 fixes call_fib_notifiers to extract the errno from the encoded
response from handlers.

Patches 2-5 allow the call to call_fib_notifiers to fail the add or
replace of a route or rule.

Patch 6 adds a simple resource controller to netdevsim to illustrate
how a FIB resource controller can limit the number of route entries.

Changes since RFC
- correct return code for call_fib_notifier
- dropped patch 6 exporting devlink symbols
- limited example resource controller to init_net only
- updated Kconfig for netdevsim to use MAY_USE_DEVLINK
- updated cover letter regarding startup case noted by Ido
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add devlink support to netdevsim and use it to implement a simple,
profile based resource controller. Only one controller is needed
per namespace, so the first netdevsim netdevice in a namespace
registers with devlink. If that device is deleted, the resource
settings are deleted.

The resource controller allows a user to limit the number of IPv4 and
IPv6 FIB entries and FIB rules. The resource paths are:
    /IPv4
    /IPv4/fib
    /IPv4/fib-rules
    /IPv6
    /IPv6/fib
    /IPv6/fib-rules

The IPv4 and IPv6 top level resources are unlimited in size and can not
be changed. From there, the number of FIB entries and FIB rule entries
are unlimited by default. A user can specify a limit for the fib and
fib-rules resources:

    $ devlink resource set netdevsim/netdevsim0 path /IPv4/fib size 96
    $ devlink resource set netdevsim/netdevsim0 path /IPv4/fib-rules size 16
    $ devlink resource set netdevsim/netdevsim0 path /IPv6/fib size 64
    $ devlink resource set netdevsim/netdevsim0 path /IPv6/fib-rules size 16
    $ devlink dev reload netdevsim/netdevsim0

such that the number of rules or routes is limited (96 ipv4 routes in the
example above):
    $ for n in $(seq 1 32); do ip ro add 10.99.$n.0/24 dev eth1; done
    Error: netdevsim: Exceeded number of supported fib entries.

    $ devlink resource show netdevsim/netdevsim0
    netdevsim/netdevsim0:
      name IPv4 size unlimited unit entry size_min 0 size_max unlimited size_gran 1 dpipe_tables non
        resources:
          name fib size 96 occ 96 unit entry size_min 0 size_max unlimited size_gran 1 dpipe_tables
    ...

With this template in place for resource management, it is fairly trivial
to extend and shows one way to implement a simple counter based resource
controller typical of network profiles.

Currently, devlink only supports initial namespace. Code is in place to
adapt netdevsim to a per namespace controller once the network namespace
issues are resolved.
Signed-off-by: NDavid Ahern <dsa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>