netdevsim: forward skbs from one connected port to another

Forward skbs sent from one netdevsim port to its connected netdevsim
port using dev_forward_skb, in a spirit similar to veth.

Add a tx_dropped variable to struct netdevsim, tracking the number of
skbs that could not be forwarded using dev_forward_skb().

The xmit() function accessing the peer ptr is protected by an RCU read
critical section. The rcu_read_lock() is functionally redundant as since
v5.0 all softirqs are implicitly RCU read critical sections; but it is
useful for human readers.

If another CPU is concurrently in nsim_destroy(), then it will first set
the peer ptr to NULL. This does not affect any existing readers that
dereferenced a non-NULL peer. Then, in unregister_netdevice(), there is
a synchronize_rcu() before the netdev is actually unregistered and
freed. This ensures that any readers i.e. xmit() that got a non-NULL
peer will complete before the netdev is freed.

Any readers after the RCU_INIT_POINTER() but before synchronize_rcu()
will dereference NULL, making it safe.

The codepath to nsim_destroy() and nsim_create() takes both the newly
added nsim_dev_list_lock and rtnl_lock. This makes it safe with
concurrent calls to linking two netdevsims together.

Signed-off-by: David Wei <dw@davidwei.uk>
Reviewed-by: Maciek Machnikowski <maciek@machnikowski.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: allow two netdevsim ports to be connected

Add two netdevsim bus attribute to sysfs:
/sys/bus/netdevsim/link_device
/sys/bus/netdevsim/unlink_device

Writing "A M B N" to link_device will link netdevsim M in netnsid A with
netdevsim N in netnsid B.

Writing "A M" to unlink_device will unlink netdevsim M in netnsid A from
its peer, if any.

rtnl_lock is taken to ensure nothing changes during the linking.

Signed-off-by: David Wei <dw@davidwei.uk>
Reviewed-by: Maciek Machnikowski <maciek@machnikowski.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: netdevsim: use mock PHC driver

I'd like to make netdevsim offload tc-taprio, but currently, this Qdisc
emits a ETHTOOL_GET_TS_INFO call to the driver to make sure that it has
a PTP clock, so that it is reasonably capable of offloading the schedule.

By using the mock PHC driver, that becomes possible.

Hardware timestamping is not necessary, and netdevsim does not support
packet I/O anyway.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20230807193324.4128292-8-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

netdevsim: add dummy macsec offload

When the kernel is compiled with MACsec support, add the
NETIF_F_HW_MACSEC feature to netdevsim devices and implement
macsec_ops.

To allow easy testing of failure from the device, support is limited
to 3 SecY's per netdevsim device, and 1 RXSC per SecY.

v2:
- nsim_macsec_add_secy, return -ENOSPC if secy_count isn't full but
we can't find an empty slot (Simon Horman)
- add sci_to_cpu to make sparse happy (Simon Horman)
- remove set but not used secy variable (kernel test robot and
Simon Horman)

Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: convert driver to use unlocked devlink API during init/fini

Prepare for devlink reload being called with devlink->lock held and
convert the netdevsim driver to use unlocked devlink API during init and
fini flows. Take devl_lock() in reload_down() and reload_up() ops in the
meantime before reload cmd is converted to take the lock itself.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

netdevsim: replace vfs_lock with devlink instance lock

Similarly to the previous commit, use the devlink instance
lock and let it replace the vfs_lock.

nsim_esw_legacy_enable() was locked by both port lock and
vfs lock so one set of lock/unlocks goes away.

netdevsim's .eswitch_mode_set callback is now ready for
the callback to take the instance lock.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: replace port_list_lock with devlink instance lock

Take advantage of the devlink instance lock for protecting
the port list. This will simplify locking even more once
all devlink callbacks hold the instance lock.

We need to add locking in nsim_dev_port_add_all() which used
to assume higher layer protection when accessing the list.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: Introduce support for L3 offload xstats

Add support for testing of HW stats support that was added recently, namely
the L3 stats support. L3 stats are provided for devices for which the L3
stats have been turned on, and that were enabled for netdevsim through a
debugfs toggle:

# echo $ifindex > /sys/kernel/debug/netdevsim/$DEV/hwstats/l3/enable_ifindex

For fully enabled netdevices, netdevsim counts 10pps of ingress traffic and
20pps of egress traffic. Similarly, L3 stats can be disabled for a given
device, and netdevsim ceases pretending there is any HW traffic going on:

# echo $ifindex > /sys/kernel/debug/netdevsim/$DEV/hwstats/l3/disable_ifindex

Besides this, there is a third toggle to mark a device for future failure:

# echo $ifindex > /sys/kernel/debug/netdevsim/$DEV/hwstats/l3/fail_next_enable

A future request to enable L3 stats on such netdevice will be bounced by
netdevsim:

# ip -j l sh dev d | jq '.[].ifindex'
66
# echo 66 > /sys/kernel/debug/netdevsim/netdevsim10/hwstats/l3/enable_ifindex
# echo 66 > /sys/kernel/debug/netdevsim/netdevsim10/hwstats/l3/fail_next_enable
# ip stats set dev d l3_stats on
Error: netdevsim: Stats enablement set to fail.

Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

netdevsim: rename 'driver' entry points

Rename functions serving as driver entry points
from nsim_dev_... to nsim_drv_... this makes the
API boundary between bus and dev clearer.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: move max vf config to dev

max_vfs is a strange little beast because the file
hangs off of nsim's debugfs, but it configures a field
in the bus device. Move it to dev.c, let's look at it
as if the device driver was imposing VF limit based
on FW info (like pci_sriov_set_totalvfs()).

Again, when moving refactor the function not to hold
the vfs lock pointlessly while parsing the input.
Wrap the access from the read side in READ_ONCE()
to appease concurrency checkers. Do not check if
return value from snprintf() is negative...

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: move details of vf config to dev

Since "eswitch" configuration was added bus.c contains
a lot of device details which really belong to dev.c.

Restructure the code while moving it.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: move vfconfig to nsim_dev

When netdevsim got split into the faux bus vfconfig ended
up in the bus device (think pci_dev) which is strange because
it contains very networky not to say netdevy information.
Move it to nsim_dev, which is the driver "priv" structure
for the device.

To make sure we don't race with probe/remove take
the device lock (much like PCI).

While at it remove the NULL-checking of vfconfigs.
It appears to be pointless.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: remove max_vfs dentry

Commit d395381909a3 ("netdevsim: Add max_vfs to bus_dev")
added this file and saved the dentry for no apparent reason.

Link: https://lore.kernel.org/r/20211028211753.22612-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

netdevsim: add ability to change channel count

For testing visibility of mq/mqprio default children.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: Protect both reload_down and reload_up paths

Don't progress with adding and deleting ports as long as devlink
reload is running.

Fixes: 23809a726c0d ("netdevsim: Forbid devlink reload when adding or deleting ports")
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: Add multi-queue support

Currently netdevsim only supports a single queue per port, which is
insufficient for testing multi-queue TC schedulers e.g. sch_mq. Extend
the current sysfs interface so that users can create ports with multiple
queues:

$ echo "[ID] [PORT_COUNT] [NUM_QUEUES]" > /sys/bus/netdevsim/new_device

As an example, echoing "2 4 8" creates 4 ports, with 8 queues per port.
Note, this is compatible with the current interface, with default number
of queues set to 1. For example, echoing "2 4" creates 4 ports with 1
queue per port; echoing "2" simply creates 1 port with 1 queue.

Reviewed-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Peilin Ye <peilin.ye@bytedance.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers: net: netdevsim: fix devlink_trap selftests failing

devlink_trap tests for the netdevsim fail due to misspelled
debugfs file name. Change this name, as well as name of callback
function, to match the naming as in the devlink itself - 'trap_drop_counter'.

Test-results:
selftests: drivers/net/netdevsim: devlink_trap.sh
TEST: Initialization [ OK ]
TEST: Trap action [ OK ]
TEST: Trap metadata [ OK ]
TEST: Non-existing trap [ OK ]
TEST: Non-existing trap action [ OK ]
TEST: Trap statistics [ OK ]
TEST: Trap group action [ OK ]
TEST: Non-existing trap group [ OK ]
TEST: Trap group statistics [ OK ]
TEST: Trap policer [ OK ]
TEST: Trap policer binding [ OK ]
TEST: Port delete [ OK ]
TEST: Device delete [ OK ]

Fixes: a7b3527a43fe ("drivers: net: netdevsim: add devlink trap_drop_counter_get implementation")
Signed-off-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Tested-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers: net: netdevsim: add devlink trap_drop_counter_get implementation

Whenever query statistics is issued for trap with DROP action,
devlink subsystem would also fill-in statistics 'dropped' field.
In case if device driver did't register callback for hard drop
statistics querying, 'dropped' field will be omitted and not filled.
Add trap_drop_counter_get callback implementation to the netdevsim.
Add new test cases for netdevsim, to test both the callback
functionality, as well as drop statistics alteration check.

Signed-off-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: Allow setting parent node of rate objects

Implement new devlink ops that allow setting rate node as a parent for
devlink port (leaf) or another devlink node through devlink API.
Expose parent names to netdevsim debugfs in read only mode.

Co-developed-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: Dmytro Linkin <dlinkin@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: Implement support for devlink rate nodes

Implement new devlink ops that allow creation, deletion and setting of
shared/max tx rate of devlink rate nodes through devlink API.
Expose rate node and it's tx rates to netdevsim debugfs.

Co-developed-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: Dmytro Linkin <dlinkin@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: Implement legacy/switchdev mode for VFs

Implement callbacks to set/get eswitch mode value. Add helpers to check
current mode.

Instantiate VFs' net devices and devlink ports on switchdev enabling and
remove them on legacy enabling. Changing number of VFs while in
switchdev mode triggers VFs creation/deletion.

Also disable NDO API callback to set VF rate, since it's legacy API.
Switchdev API to set VF rate will be implemented in one of the next
patches.

Signed-off-by: Dmytro Linkin <dlinkin@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: Implement port types and indexing

Define type of ports, which netdevsim driver currently operates with as
PF. Define new port type - VF, which will be implemented in following
patches. Add helper functions to distinguish them. Add helper function
to get VF index from port index.

Add port indexing logic where PFs' indexes starts from 0, VFs' - from
NSIM_DEV_VF_PORT_INDEX_BASE.
All ports uses same index pool, which means that PF port may be created
with index from VFs' indexes range.
Maximum number of VFs, which the driver can allocate, is limited by
UINT_MAX - BASE.

Signed-off-by: Dmytro Linkin <dlinkin@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: Disable VFs on nsim_dev_reload_destroy() call

Move VFs disabling from device release() to nsim_dev_reload_destroy() to
make VFs disabling and ports removal simultaneous.
This is a requirement for VFs ports implemented in next patches.

Signed-off-by: Dmytro Linkin <dlinkin@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: Add max_vfs to bus_dev

Currently there is no limit to the number of VFs netdevsim can enable.
In a real systems this value exist and used by the driver.
Fore example, some features might need to consider this value when
allocating memory.

Expose max_vfs variable to debugfs as configurable resource. If are VFs
configured (num_vfs != 0) then changing of max_vfs not allowed.

Co-developed-by: Yuval Avnery <yuvalav@nvidia.com>
Signed-off-by: Yuval Avnery <yuvalav@nvidia.com>
Signed-off-by: Dmytro Linkin <dlinkin@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: add FEC settings support

Add support for ethtool FEC and some ethtool error injection.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: Add dummy psample implementation

Allow netdevsim to report "sampled" packets to the psample module by
periodically generating packets from a work queue. The behavior can be
enabled / disabled (default) and the various meta data attributes can be
controlled via debugfs knobs.

This implementation enables both testing of the psample module with all
the optional attributes as well as development of user space
applications on top of psample such as hsflowd and a Wireshark dissector
for psample generic netlink packets.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: Add debugfs toggle to reject BPF programs in verifier

This adds a new debugfs toggle ('bpf_bind_verifier_accept') that can be
used to make netdevsim reject BPF programs from being accepted by the
verifier. If this toggle (which defaults to true) is set to false,
nsim_bpf_verify_insn() will return EOPNOTSUPP on the last
instruction (after outputting the 'Hello from netdevsim' verifier message).

This makes it possible to check the verification callback in the driver
from test_offload.py in selftests, since the verifier now clears the
verifier log on a successful load, hiding the message from the driver.

Fixes: 6f8a57ccf851 ("bpf: Make verifier log more relevant by default")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/bpf/160752225964.110217.12584017165318065332.stgit@toke.dk

netdevsim: support ethtool ring and coalesce settings

Add ethtool ring and coalesce settings support for testing.

Signed-off-by: Antonio Cardace <acardace@redhat.com>
Reviewed-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

netdevsim: move ethtool pause params in separate struct

This will help the refactoring in the next commit
when coalesce and ring settings are added.

Signed-off-by: Antonio Cardace <acardace@redhat.com>
Reviewed-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

netdevsim: Add devlink resource for nexthops

The Spectrum ASIC has a dedicated table where nexthops (i.e., adjacency
entries) are populated. The size of this table can be controlled via
devlink-resource.

Add such a resource to netdevsim so that its occupancy will reflect the
number of nexthop objects currently programmed to the device.

By limiting the size of the resource, error paths could be exercised and
tested.

Example output:

# devlink resource show netdevsim/netdevsim10
netdevsim/netdevsim10:
name IPv4 size unlimited unit entry size_min 0 size_max unlimited size_gran 1 dpipe_tables none
resources:
name fib size unlimited occ 4 unit entry size_min 0 size_max unlimited size_gran 1 dpipe_tables none
name fib-rules size unlimited occ 3 unit entry size_min 0 size_max unlimited size_gran 1 dpipe_tables none
name IPv6 size unlimited unit entry size_min 0 size_max unlimited size_gran 1 dpipe_tables none
resources:
name fib size unlimited occ 1 unit entry size_min 0 size_max unlimited size_gran 1 dpipe_tables none
name fib-rules size unlimited occ 2 unit entry size_min 0 size_max unlimited size_gran 1 dpipe_tables none
name nexthops size unlimited occ 0 unit entry size_min 0 size_max unlimited size_gran 1 dpipe_tables none

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

netdevsim: support the static IANA VXLAN port flag

Allow setting UDP_TUNNEL_NIC_INFO_STATIC_IANA_VXLAN.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: shared UDP tunnel port table support

Add the ability to simulate a device with a shared UDP tunnel port
table.

Try to reject the configurations and actions which are not supported
by the core, so we don't get syzcaller etc. warning reports.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: add support for flash_update overwrite mask

The devlink interface recently gained support for a new "overwrite mask"
parameter that allows specifying how various sub-sections of a flash
component are modified when updating.

Add support for this to netdevsim, to enable easily testing the
interface. Make the allowed overwrite mask values controllable via
a debugfs parameter. This enables testing a flow where the driver
rejects an unsupportable overwrite mask.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: add pause frame stats

Add minimal ethtool interface for testing ethtool pause stats.

v2: add missing static on nsim_ethtool_ops

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

bpf, xdp: Remove XDP_QUERY_PROG and XDP_QUERY_PROG_HW XDP commands

Now that BPF program/link management is centralized in generic net_device
code, kernel code never queries program id from drivers, so
XDP_QUERY_PROG/XDP_QUERY_PROG_HW commands are unnecessary.

This patch removes all the implementations of those commands in kernel, along
the xdp_attachment_query().

This patch was compile-tested on allyesconfig.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200722064603.3350758-10-andriin@fb.com

netdevsim: add UDP tunnel port offload support

Add UDP tunnel port handlers to our fake driver so we can test
the core infra.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: Add support for setting of packet trap group parameters

Add a dummy callback to set trap group parameters. Return an error when
the 'fail_trap_group_set' debugfs file is set in order to exercise error
paths and verify that error is propagated to user space when should.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: Add devlink-trap policer support

Register three dummy packet trap policers with devlink and implement
callbacks to change their parameters and read their counters.

This will be used later on in the series to test the devlink-trap
policer infrastructure.

v2:
* Remove check about burst size being a power of 2 and instead add a
debugfs knob to fail the operation
* Provide max/min rate/burst size when registering policers and remove
the validity checks from nsim_dev_devlink_trap_policer_set()

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: add ACL trap reporting cookie as a metadata

Add new trap ACL which reports flow action cookie in a metadata. Allow
used to setup the cookie using debugfs file.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: fix panic in nsim_dev_take_snapshot_write()

nsim_dev_take_snapshot_write() uses nsim_dev and nsim_dev->dummy_region.
So, during this function, these data shouldn't be removed.
But there is no protecting stuff in this function.

There are two similar cases.
1. reload case
reload could be called during nsim_dev_take_snapshot_write().
When reload is being executed, nsim_dev_reload_down() is called and it
calls nsim_dev_reload_destroy(). nsim_dev_reload_destroy() calls
devlink_region_destroy() to destroy nsim_dev->dummy_region.
So, during nsim_dev_take_snapshot_write(), nsim_dev->dummy_region()
would be removed.
At this point, snapshot_write() would access freed pointer.
In order to fix this case, take_snapshot file will be removed before
devlink_region_destroy().
The take_snapshot file will be re-created by ->reload_up().

2. del_device_store case
del_device_store() also could call nsim_dev_reload_destroy()
during nsim_dev_take_snapshot_write(). If so, panic would occur.
This problem is actually the same problem with the first case.
So, this problem will be fixed by the first case's solution.

Test commands:
modprobe netdevsim
while :
do
echo 1 > /sys/bus/netdevsim/new_device &
echo 1 > /sys/bus/netdevsim/del_device &
devlink dev reload netdevsim/netdevsim1 &
echo 1 > /sys/kernel/debug/netdevsim/netdevsim1/take_snapshot &
done

Splat looks like:
[ 45.564513][ T975] general protection fault, probably for non-canonical address 0xdffffc000000003a: 0000 [#1] SMP DEI
[ 45.566131][ T975] KASAN: null-ptr-deref in range [0x00000000000001d0-0x00000000000001d7]
[ 45.566135][ T975] CPU: 1 PID: 975 Comm: bash Not tainted 5.5.0+ #322
[ 45.569020][ T975] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[ 45.569026][ T975] RIP: 0010:__mutex_lock+0x10a/0x14b0
[ 45.570518][ T975] Code: 08 84 d2 0f 85 7f 12 00 00 44 8b 0d 10 23 65 02 45 85 c9 75 29 49 8d 7f 68 48 b8 00 00 00 0f
[ 45.570522][ T975] RSP: 0018:ffff888046ccfbf0 EFLAGS: 00010206
[ 45.572305][ T975] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
[ 45.572308][ T975] RDX: 000000000000003a RSI: ffffffffac926440 RDI: 00000000000001d0
[ 45.576843][ T975] RBP: ffff888046ccfd70 R08: ffffffffab610645 R09: 0000000000000000
[ 45.576847][ T975] R10: ffff888046ccfd90 R11: ffffed100d6360ad R12: 0000000000000000
[ 45.578471][ T975] R13: dffffc0000000000 R14: ffffffffae1976c0 R15: 0000000000000168
[ 45.578475][ T975] FS: 00007f614d6e7740(0000) GS:ffff88806c400000(0000) knlGS:0000000000000000
[ 45.581492][ T975] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 45.582942][ T975] CR2: 00005618677d1cf0 CR3: 000000005fb9c002 CR4: 00000000000606e0
[ 45.584543][ T975] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 45.586633][ T975] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 45.589889][ T975] Call Trace:
[ 45.591445][ T975] ? devlink_region_snapshot_create+0x55/0x4a0
[ 45.601250][ T975] ? mutex_lock_io_nested+0x1380/0x1380
[ 45.602817][ T975] ? mutex_lock_io_nested+0x1380/0x1380
[ 45.603875][ T975] ? mark_held_locks+0xa5/0xe0
[ 45.604769][ T975] ? _raw_spin_unlock_irqrestore+0x2d/0x50
[ 45.606147][ T975] ? __mutex_unlock_slowpath+0xd0/0x670
[ 45.607723][ T975] ? crng_backtrack_protect+0x80/0x80
[ 45.613530][ T975] ? wait_for_completion+0x390/0x390
[ 45.615152][ T975] ? devlink_region_snapshot_create+0x55/0x4a0
[ 45.616834][ T975] devlink_region_snapshot_create+0x55/0x4a0
[ ... ]

Fixes: 4418f862d675 ("netdevsim: implement support for devlink region and snapshots")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

netdevsim: disable devlink reload when resources are being used

devlink reload destroys resources and allocates resources again.
So, when devices and ports resources are being used, devlink reload
function should not be executed. In order to avoid this race, a new
lock is added and new_port() and del_port() call devlink_reload_disable()
and devlink_reload_enable().

Thread0 Thread1
{new/del}_port() {new/del}_port()
devlink_reload_disable()
devlink_reload_disable()
devlink_reload_enable()
//here
devlink_reload_enable()

Before Thread1's devlink_reload_enable(), the devlink is already allowed
to execute reload because Thread0 allows it. devlink reload disable/enable
variable type is bool. So the above case would exist.
So, disable/enable should be executed atomically.
In order to do that, a new lock is used.

Test commands:
modprobe netdevsim
echo 1 > /sys/bus/netdevsim/new_device
while :
do
echo 1 > /sys/devices/netdevsim1/new_port &
echo 1 > /sys/devices/netdevsim1/del_port &
devlink dev reload netdevsim/netdevsim1 &
done

Splat looks like:
[ 23.342145][ T932] DEBUG_LOCKS_WARN_ON(mutex_is_locked(lock))
[ 23.342159][ T932] WARNING: CPU: 0 PID: 932 at kernel/locking/mutex-debug.c:103 mutex_destroy+0xc7/0xf0
[ 23.344182][ T932] Modules linked in: netdevsim openvswitch nsh nf_conncount nf_nat nf_conntrack nf_defrag_ipv6 nf_dx
[ 23.346485][ T932] CPU: 0 PID: 932 Comm: devlink Not tainted 5.5.0+ #322
[ 23.347696][ T932] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[ 23.348893][ T932] RIP: 0010:mutex_destroy+0xc7/0xf0
[ 23.349505][ T932] Code: e0 07 83 c0 03 38 d0 7c 04 84 d2 75 2e 8b 05 00 ac b0 02 85 c0 75 8b 48 c7 c6 00 5e 07 96 40
[ 23.351887][ T932] RSP: 0018:ffff88806208f810 EFLAGS: 00010286
[ 23.353963][ T932] RAX: dffffc0000000008 RBX: ffff888067f6f2c0 RCX: ffffffff942c4bd4
[ 23.355222][ T932] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff96dac5b4
[ 23.356169][ T932] RBP: ffff888067f6f000 R08: fffffbfff2d235a5 R09: fffffbfff2d235a5
[ 23.357160][ T932] R10: 0000000000000001 R11: fffffbfff2d235a4 R12: ffff888067f6f208
[ 23.358288][ T932] R13: ffff88806208fa70 R14: ffff888067f6f000 R15: ffff888069ce3800
[ 23.359307][ T932] FS: 00007fe2a3876740(0000) GS:ffff88806c000000(0000) knlGS:0000000000000000
[ 23.360473][ T932] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 23.361319][ T932] CR2: 00005561357aa000 CR3: 000000005227a006 CR4: 00000000000606f0
[ 23.362323][ T932] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 23.363417][ T932] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 23.364414][ T932] Call Trace:
[ 23.364828][ T932] nsim_dev_reload_destroy+0x77/0xb0 [netdevsim]
[ 23.365655][ T932] nsim_dev_reload_down+0x84/0xb0 [netdevsim]
[ 23.366433][ T932] devlink_reload+0xb1/0x350
[ 23.367010][ T932] genl_rcv_msg+0x580/0xe90

[ ...]

[ 23.531729][ T1305] kernel BUG at lib/list_debug.c:53!
[ 23.532523][ T1305] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI
[ 23.533467][ T1305] CPU: 2 PID: 1305 Comm: bash Tainted: G W 5.5.0+ #322
[ 23.534962][ T1305] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[ 23.536503][ T1305] RIP: 0010:__list_del_entry_valid+0xe6/0x150
[ 23.538346][ T1305] Code: 89 ea 48 c7 c7 00 73 1e 96 e8 df f7 4c ff 0f 0b 48 c7 c7 60 73 1e 96 e8 d1 f7 4c ff 0f 0b 44
[ 23.541068][ T1305] RSP: 0018:ffff888047c27b58 EFLAGS: 00010282
[ 23.542001][ T1305] RAX: 0000000000000054 RBX: ffff888067f6f318 RCX: 0000000000000000
[ 23.543051][ T1305] RDX: 0000000000000054 RSI: 0000000000000008 RDI: ffffed1008f84f61
[ 23.544072][ T1305] RBP: ffff88804aa0fca0 R08: ffffed100d940539 R09: ffffed100d940539
[ 23.545085][ T1305] R10: 0000000000000001 R11: ffffed100d940538 R12: ffff888047c27cb0
[ 23.546422][ T1305] R13: ffff88806208b840 R14: ffffffff981976c0 R15: ffff888067f6f2c0
[ 23.547406][ T1305] FS: 00007f76c0431740(0000) GS:ffff88806c800000(0000) knlGS:0000000000000000
[ 23.548527][ T1305] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 23.549389][ T1305] CR2: 00007f5048f1a2f8 CR3: 000000004b310006 CR4: 00000000000606e0
[ 23.550636][ T1305] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 23.551578][ T1305] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 23.552597][ T1305] Call Trace:
[ 23.553004][ T1305] mutex_remove_waiter+0x101/0x520
[ 23.553646][ T1305] __mutex_lock+0xac7/0x14b0
[ 23.554218][ T1305] ? nsim_dev_port_del+0x4e/0x140 [netdevsim]
[ 23.554908][ T1305] ? mutex_lock_io_nested+0x1380/0x1380
[ 23.555570][ T1305] ? _parse_integer+0xf0/0xf0
[ 23.556043][ T1305] ? kstrtouint+0x86/0x110
[ 23.556504][ T1305] ? nsim_dev_port_del+0x4e/0x140 [netdevsim]
[ 23.557133][ T1305] nsim_dev_port_del+0x4e/0x140 [netdevsim]
[ 23.558024][ T1305] del_port_store+0xcc/0xf0 [netdevsim]
[ ... ]

Fixes: 75ba029f3c07 ("netdevsim: implement proper devlink reload")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

netdevsim: fix using uninitialized resources

When module is being initialized, __init() calls bus_register() and
driver_register().
These functions internally create various resources and sysfs files.
The sysfs files are used for basic operations(add/del device).
/sys/bus/netdevsim/new_device
/sys/bus/netdevsim/del_device

These sysfs files use netdevsim resources, they are mostly allocated
and initialized in ->probe() function, which is nsim_dev_probe().
But, sysfs files could be executed before ->probe() is finished.
So, accessing uninitialized data would occur.

Another problem is very similar.
/sys/bus/netdevsim/new_device internally creates sysfs files.
/sys/devices/netdevsim<id>/new_port
/sys/devices/netdevsim<id>/del_port

These sysfs files also use netdevsim resources, they are mostly allocated
and initialized in creating device routine, which is nsim_bus_dev_new().
But they also could be executed before nsim_bus_dev_new() is finished.
So, accessing uninitialized data would occur.

To fix these problems, this patch adds flags, which means whether the
operation is finished or not.
The flag variable 'nsim_bus_enable' means whether netdevsim bus was
initialized or not.
This is protected by nsim_bus_dev_list_lock.
The flag variable 'nsim_bus_dev->init' means whether nsim_bus_dev was
initialized or not.
This could be used in {new/del}_port_store() with no lock.

Test commands:
#SHELL1
modprobe netdevsim
while :
do
echo "1 1" > /sys/bus/netdevsim/new_device
echo "1 1" > /sys/bus/netdevsim/del_device
done

#SHELL2
while :
do
echo 1 > /sys/devices/netdevsim1/new_port
echo 1 > /sys/devices/netdevsim1/del_port
done

Splat looks like:
[ 47.508954][ T1008] general protection fault, probably for non-canonical address 0xdffffc0000000021: 0000 I
[ 47.510793][ T1008] KASAN: null-ptr-deref in range [0x0000000000000108-0x000000000000010f]
[ 47.511963][ T1008] CPU: 2 PID: 1008 Comm: bash Not tainted 5.5.0+ #322
[ 47.512823][ T1008] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[ 47.514041][ T1008] RIP: 0010:__mutex_lock+0x10a/0x14b0
[ 47.514699][ T1008] Code: 08 84 d2 0f 85 7f 12 00 00 44 8b 0d 10 23 65 02 45 85 c9 75 29 49 8d 7f 68 48 b8 00 00 00 0f
[ 47.517163][ T1008] RSP: 0018:ffff888059b4fbb0 EFLAGS: 00010206
[ 47.517802][ T1008] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
[ 47.518941][ T1008] RDX: 0000000000000021 RSI: ffffffff85926440 RDI: 0000000000000108
[ 47.519732][ T1008] RBP: ffff888059b4fd30 R08: ffffffffc073fad0 R09: 0000000000000000
[ 47.520729][ T1008] R10: ffff888059b4fd50 R11: ffff88804bb38040 R12: 0000000000000000
[ 47.521702][ T1008] R13: dffffc0000000000 R14: ffffffff871976c0 R15: 00000000000000a0
[ 47.522760][ T1008] FS: 00007fd4be05a740(0000) GS:ffff88806c800000(0000) knlGS:0000000000000000
[ 47.523877][ T1008] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 47.524627][ T1008] CR2: 0000561c82b69cf0 CR3: 0000000065dd6004 CR4: 00000000000606e0
[ 47.527662][ T1008] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 47.528604][ T1008] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 47.529531][ T1008] Call Trace:
[ 47.529874][ T1008] ? nsim_dev_port_add+0x50/0x150 [netdevsim]
[ 47.530470][ T1008] ? mutex_lock_io_nested+0x1380/0x1380
[ 47.531018][ T1008] ? _kstrtoull+0x76/0x160
[ 47.531449][ T1008] ? _parse_integer+0xf0/0xf0
[ 47.531874][ T1008] ? kernfs_fop_write+0x1cf/0x410
[ 47.532330][ T1008] ? sysfs_file_ops+0x160/0x160
[ 47.532773][ T1008] ? kstrtouint+0x86/0x110
[ 47.533168][ T1008] ? nsim_dev_port_add+0x50/0x150 [netdevsim]
[ 47.533721][ T1008] nsim_dev_port_add+0x50/0x150 [netdevsim]
[ 47.534336][ T1008] ? sysfs_file_ops+0x160/0x160
[ 47.534858][ T1008] new_port_store+0x99/0xb0 [netdevsim]
[ 47.535439][ T1008] ? del_port_store+0xb0/0xb0 [netdevsim]
[ 47.536035][ T1008] ? sysfs_file_ops+0x112/0x160
[ 47.536544][ T1008] ? sysfs_kf_write+0x3b/0x180
[ 47.537029][ T1008] kernfs_fop_write+0x276/0x410
[ 47.537548][ T1008] ? __sb_start_write+0x215/0x2e0
[ 47.538110][ T1008] vfs_write+0x197/0x4a0
[ ... ]

Fixes: f9d9db47d3ba ("netdevsim: add bus attributes to add new and delete devices")
Fixes: 794b2c05ca1c ("netdevsim: extend device attrs to support port addition and deletion")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

netdevsim: implement couple of testing devlink health reporters

Implement "empty" and "dummy" reporters. The first one is really simple
and does nothing. The other one has debugfs files to trigger breakage
and it is able to do recovery. The ops also implement dummy fmsg
content.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: add couple of debugfs bools to debug devlink reload

Add flag to disallow reload and another one that causes reload to
always fail.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: create devlink and netdev instances in namespace

When user does create new netdevsim instance using sysfs bus file,
create the devlink instance and related netdev instance in the namespace
of the caller.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: register port netdevices into net of device

Register newly created port netdevice into net namespace
that the parent device belongs to.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: implement proper devlink reload

During devlink reload, all driver objects should be reinstantiated with
the exception of devlink instance and devlink resources and params.
Move existing devlink_resource_size_get() calls into fib_create() just
before fib notifier is registered. Also, make sure that extack is
propagated down to fib_notifier_register() call.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: change fib accounting and limitations to be per-device

Currently, the accounting is done per-namespace. However, devlink
instance is always in init_net namespace for now, so only the accounting
related to init_net is used. Limitations set using devlink resources
are only considered for init_net. nsim_devlink_net() always
returns init_net always.

Make the accounting per-device. This brings no functional change.
Per-device accounting has the same values as per-net.
For a single netdevsim instance, the behaviour is exactly the same
as before. When multiple netdevsim instances are created, each
can have different limits.

This is in prepare to implement proper devlink netns support. After
that, the devlink instance which would exist in particular netns would
account and limit that netns.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: Add devlink-trap support

Have netdevsim register its trap groups and traps with devlink during
initialization and periodically report trapped packets to devlink core.

Since netdevsim is not a real device, the trapped packets are emulated
using a workqueue that periodically reports a UDP packet with a random
5-tuple from each active packet trap and from each running netdev.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: implement support for devlink region and snapshots

Implement dummy region of size 32K and allow user to create snapshots
or random data using debugfs file trigger.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: register couple of devlink params

Register couple of devlink params, one generic, one driver-specific.
Make the values available over debugfs.

Example:
$ echo "111" > /sys/bus/netdevsim/new_device
$ devlink dev param
netdevsim/netdevsim111:
name max_macs type generic
values:
cmode driverinit value 32
name test1 type driver-specific
values:
cmode driverinit value true
$ cat /sys/kernel/debug/netdevsim/netdevsim111/max_macs
32
$ cat /sys/kernel/debug/netdevsim/netdevsim111/test1
Y
$ devlink dev param set netdevsim/netdevsim111 name max_macs cmode driverinit value 16
$ devlink dev param set netdevsim/netdevsim111 name test1 cmode driverinit value false
$ devlink dev reload netdevsim/netdevsim111
$ cat /sys/kernel/debug/netdevsim/netdevsim111/max_macs
16
$ cat /sys/kernel/debug/netdevsim/netdevsim111/test1

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: Restore per-network namespace accounting for fib entries

Prior to the commit in the fixes tag, the resource controller in netdevsim
tracked fib entries and rules per network namespace. Restore that behavior.

Fixes: 5fc494225c1e ("netdevsim: create devlink instance per netdevsim instance")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: implement fake flash updating with notifications

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: move netdev creation/destruction to dev probe

Remove the existing way to create netdevsim over rtnetlink and move the
netdev creation/destruction to dev probe, so for every probed port,
a netdevsim-netdev instance is created.

Adjust selftests to work with new interface.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: extend device attrs to support port addition and deletion

In order to test flows in core, it is beneficial to maintain previously
supported possibility to add and delete ports during netdevsim lifetime.
Do it by extending device sysfs attrs by "new_port" and "del_port".

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: implement dev probe/remove skeleton with port initialization

Implement netdevsim bus probing of netdevsim devices. For every probed
device create a devlink instance. According to the user-passed value,
create a number of ports represented by devlink port instances.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: change debugfs tree topology

With the model where dev is represented by devlink and ports are
represented by devlink ports, make debugfs file names independent
on netdev names. Change the topology to the one illustrated
by the following example:

$ ls /sys/kernel/debug/netdevsim/
netdevsim1
$ ls /sys/kernel/debug/netdevsim/netdevsim1/
bpf_bind_accept bpf_bind_verifier_delay bpf_bound_progs ports
$ ls /sys/kernel/debug/netdevsim/netdevsim1/ports/
0 1
$ ls /sys/kernel/debug/netdevsim/netdevsim1/ports/0/
bpf_map_accept bpf_offloaded_id bpf_tc_accept bpf_tc_non_bound_accept bpf_xdpdrv_accept bpf_xdpoffload_accept dev ipsec
$ ls /sys/kernel/debug/netdevsim/netdevsim1/ports/0/dev -l
lrwxrwxrwx 1 root root 0 Apr 13 15:58 /sys/kernel/debug/netdevsim/netdevsim1/ports/0/dev -> ../../../netdevsim1

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: generate random switch id instead of using dev id

Current implementation of parent_id/switch_id does not follow the
original idea of being unique. The values are "0", "1", etc. Instead of
that, generate 32 random bytes.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: merge sdev into dev

As previously introduce dev which is mapped 1:1 to a bus device covers
the purpose of the original shared device, merge the sdev code into dev.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: rename dev_init/exit() functions and make them independent on ns

These functions are going to be called from bus probe/release(),
therefore make them independent on ns struct and rename accordingly.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: add bus attributes to add new and delete devices

Add a way to add new netdevsim device on netdevsim bus and also to
delete existing netdevsim device from the bus. Track the bus devices
in using a list.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: move device registration and related code to bus.c

Move netdevsim device registration into bus.c and alongside with that
the related sysfs attributes. Introduce new struct nsim_bus_dev to
represent a netdevsim device on netdevsim bus.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: put netdevsim bus code into separate file

As the code related to netdevsim bus is going to get bigger, move the
existing code to a separate file.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: rename devlink.c to dev.c to contain per-dev(asic) items

The existing devlink.c code is going to be extended to represent asic
device on a bus. As this is about more than just devlink,
rename the file. Do appropriate prefix renaming alongside with that.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: create devlink instance per netdevsim instance

Currently there is one devlink instance created per network namespace.
That is quite odd considering the fact that devlink instance should
represent an ASIC. The following patches are going to move the devlink
instance even more down to a bus device, but until then, have one
devlink instance per netdevsim instance. Struct nsim_devlink is
introduced to hold fib setting.

The changes in the fib code are only related to holding the
configuration per devlink instance instead of network namespace.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: move sdev specific bpf debugfs files to sdev dir

Some netdevsim bpf debugfs files are per-sdev, yet they are defined per
netdevsim instance. Move them under sdev directory.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: move shared dev creation and destruction into separate file

To make code easier to read, move shared dev bits into a separate file.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: assume CONFIG_NET_DEVLINK is always enabled

Since commit f6b19b354d50 ("net: devlink: select NET_DEVLINK
from drivers") adds implicit select of NET_DEVLINK for
netdevsim, the code does not have to deal with the case
when CONFIG_NET_DEVLINK is not enabled. So remove the ifcase.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: make debug dirs' dentries static

The root directories of netdevsim should only be used by the core
to create per-device subdirectories, so limit their visibility to
the core file.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

bpf: offload: keep the offload state per-ASIC

Create a higher-level entity to represent a device/ASIC to allow
programs and maps to be shared between device ports. The extra
work is required to make sure we don't destroy BPF objects as
soon as the netdev for which they were loaded gets destroyed,
as other ports may still be using them. When netdev goes away
all of its BPF objects will be moved to other netdevs of the
device, and only destroyed when last netdev is unregistered.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

netdevsim: associate bound programs with shared dev

Move bound program information from netdevsim to shared sub-object,
as programs will soon be shared between netdevs of the same ASIC.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

netdevsim: add shared netdevsim devices

Factor out sharable netdevsim sub-object and use IFLA_LINK to link
netdevsims together at creation time. Sharable object will have
its own DebugFS directory.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

netdevsim: add switch_id attribute

Grouping netdevsim devices into "ASICs" will soon be supported.
Add switch_id attribute to all netdevsims. For now each netdevsim
will have its switch_id matching the device id.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

netdevsim: add support for simultaneous driver and hw XDP

Allow netdevsim to accept driver and offload attachment of XDP
BPF programs at the same time.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

xdp: factor out common program/flags handling from drivers

Basic operations drivers perform during xdp setup and query can
be moved to helpers in the core. Encapsulate program and flags
into a structure and add helpers. Note that the structure is
intended as the "main" program information source in the driver.
Most drivers will additionally place the program pointer in their
fast path or ring structures.

The helpers don't have a huge impact now, but they will
decrease the code duplication when programs can be installed
in HW and driver at the same time. Encapsulating the basic
operations in helpers will hopefully also reduce the number
of changes to drivers which adopt them.

Helpers could really be static inline, but they depend on
definition of struct netdev_bpf which means they'd have
to be placed in netdevice.h, an already 4500 line header.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

netdevsim: add ipsec offload testing

Implement the IPsec/XFRM offload API for testing.

Signed-off-by: Shannon Nelson <shannon.nelson@oracle.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: Add extack error message for devlink reload

devlink reset command can fail if a FIB resource limit is set to a value
lower than the current occupancy. Return a proper message indicating the
reason for the failure.

$ devlink resource sh netdevsim/netdevsim0
netdevsim/netdevsim0:
name IPv4 size unlimited unit entry size_min 0 size_max unlimited size_gran 1 dpipe_tables none
resources:
name fib size unlimited occ 43 unit entry size_min 0 size_max unlimited size_gran 1 dpipe_tables none
name fib-rules size unlimited occ 4 unit entry size_min 0 size_max unlimited size_gran 1 dpipe_tables none
name IPv6 size unlimited unit entry size_min 0 size_max unlimited size_gran 1 dpipe_tables none
resources:
name fib size unlimited occ 54 unit entry size_min 0 size_max unlimited size_gran 1 dpipe_tables none
name fib-rules size unlimited occ 3 unit entry size_min 0 size_max unlimited size_gran 1 dpipe_tables none

$ devlink resource set netdevsim/netdevsim0 path /IPv4/fib size 40

$ devlink dev reload netdevsim/netdevsim0
Error: netdevsim: New size is less than current occupancy.
devlink answers: Invalid argument

Signed-off-by: David Ahern <dsahern@gmail.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: Change nsim_devlink_setup to return error to caller

Change nsim_devlink_setup to return any error back to the caller and
update nsim_init to handle it.

Requested-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: Add simple FIB resource controller via devlink

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: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: don't compile BPF code if syscall not enabled

We should not compile netdevsim/bpf.c if BPF syscall is not
enabled. Otherwise bpf core would have to provide wrappers
for all functions offload drivers may call, even though
system will never see a BPF object.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netdevsim: bpf: support fake map offload

Add to netdevsim ability to pretend it's offloading BPF maps.
We only allow allocation of tiny 2 entry maps, to keep things
simple. Mutex lock may seem heavy for the operations we
perform, but we want to make sure callbacks can sleep.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

netdevsim: add SR-IOV functionality

dummy driver was extended with VF-related netdev APIs for testing
SR-IOV-related software. netdevsim did not exist back then.
Implement SR-IOV functionality in netdevsim. Notable difference
is that since netdevsim has no module parameters, we will actually
create a device with sriov_numvfs attribute for each netdev.
The zero MAC address is accepted as some HW use it to mean any
address is allowed. Link state is also now validated.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

netdevsim: add bpf offload support

Add support for loading programs for netdevsim devices and
expose the related information via DebugFS. Both offload
of XDP and cls_bpf programs is supported.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

netdevsim: add software driver for testing offloads

To be able to run selftests without any hardware required we
need a software model. The model can also serve as an example
implementation for those implementing actual HW offloads.
The dummy driver have previously been extended to test SR-IOV,
but the general consensus seems to be against adding further
features to it.

Add a new driver for purposes of software modelling only.
eBPF and SR-IOV will be added here shortly, others are invited
to further extend the driver with their offload models.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>