linux-toradex.git/drivers/net/netdevsim, branch v4.17

devlink: convert occ_get op to separate registration

2018-04-08T16:45:57+00:00

This resolves race during initialization where the resources with
ops are registered before driver and the structures used by occ_get
op is initialized. So keep occ_get callbacks registered only when
all structs are initialized.

The example flows, as it is in mlxsw:
1) driver load/asic probe:
   mlxsw_core
      -> mlxsw_sp_resources_register
        -> mlxsw_sp_kvdl_resources_register
          -> devlink_resource_register IDX
   mlxsw_spectrum
      -> mlxsw_sp_kvdl_init
        -> mlxsw_sp_kvdl_parts_init
          -> mlxsw_sp_kvdl_part_init
            -> devlink_resource_size_get IDX (to get the current setup
                                              size from devlink)
        -> devlink_resource_occ_get_register IDX (register current
                                                  occupancy getter)
2) reload triggered by devlink command:
  -> mlxsw_devlink_core_bus_device_reload
    -> mlxsw_sp_fini
      -> mlxsw_sp_kvdl_fini
	-> devlink_resource_occ_get_unregister IDX
    (struct mlxsw_sp *mlxsw_sp is freed at this point, call to occ get
     which is using mlxsw_sp would cause use-after free)
    -> mlxsw_sp_init
      -> mlxsw_sp_kvdl_init
        -> mlxsw_sp_kvdl_parts_init
          -> mlxsw_sp_kvdl_part_init
            -> devlink_resource_size_get IDX (to get the current setup
                                              size from devlink)
        -> devlink_resource_occ_get_register IDX (register current
                                                  occupancy getter)

Fixes: d9f9b9a4d05f ("devlink: Add support for resource abstraction")
Signed-off-by: Jiri Pirko 
Signed-off-by: David S. Miller

netdevsim: remove incorrect __net_initdata annotations

2018-04-04T16:53:37+00:00

The __net_initdata section cannot currently be used for structures that
get cleaned up in an exitcall using unregister_pernet_operations:

WARNING: vmlinux.o(.text+0x868c34): Section mismatch in reference from the function nsim_devlink_exit() to the (unknown reference) .init.data:(unknown)
The function nsim_devlink_exit() references
the (unknown reference) __initdata (unknown).
This is often because nsim_devlink_exit lacks a __initdata
annotation or the annotation of (unknown) is wrong.
WARNING: vmlinux.o(.text+0x868c64): Section mismatch in reference from the function nsim_devlink_init() to the (unknown reference) .init.data:(unknown)
WARNING: vmlinux.o(.text+0x8692bc): Section mismatch in reference from the function nsim_fib_exit() to the (unknown reference) .init.data:(unknown)
WARNING: vmlinux.o(.text+0x869300): Section mismatch in reference from the function nsim_fib_init() to the (unknown reference) .init.data:(unknown)

As that warning tells us, discarding the structure after a module is
loaded would lead to a undefined behavior when that module is removed.

It might be possible to change that annotation so it has no effect for
loadable modules, but I have not figured out exactly how to do that, and
we want this to be fixed in -rc1.

This just removes the annotations, just like we do for all other such
modules.

Fixes: 37923ed6b8ce ("netdevsim: Add simple FIB resource controller via devlink")
Signed-off-by: Arnd Bergmann 
Signed-off-by: David S. Miller

netdevsim: Change nsim_devlink_setup to return error to caller

2018-04-01T02:22:10+00:00

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

Requested-by: Jakub Kicinski 
Signed-off-by: David Ahern 
Acked-by: Jakub Kicinski 
Signed-off-by: David S. Miller

netdevsim: Add simple FIB resource controller via devlink

2018-03-29T18:10:31+00:00

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
Signed-off-by: David S. Miller

netdevsim: fix overflow on the error path

2018-02-01T10:22:51+00:00

Undo loop condition on the error path would cause the i counter
to go below zero, if allocation failure happened with the first
(i.e. 0th) element of the array.

Fixes: 395cacb5f1a0 ("netdevsim: bpf: support fake map offload")
Reported-by: Dan Carpenter 
Signed-off-by: Jakub Kicinski 
Reviewed-by: Simon Horman 
Signed-off-by: Daniel Borkmann

netdevsim: use tc_cls_can_offload_and_chain0()

2018-01-26T02:23:08+00:00

Make use of tc_cls_can_offload_and_chain0() to set extack msg in case
ethtool tc offload flag is not set or chain unsupported.

Signed-off-by: Jakub Kicinski 
Reviewed-by: Simon Horman 
Signed-off-by: David S. Miller

selftests/bpf: check bpf verifier log buffer usage works for HW offload

2018-01-24T01:24:31+00:00

Make netdevsim print a message to the BPF verifier log buffer when a
program is offloaded.

Then use this message in hardware offload selftests to make sure that
using this buffer actually prints the message to the console for
eBPF hardware offload.

The message is appended after the last instruction is processed with the
verifying function from netdevsim. Output looks like the following:

    $ tc filter add dev foo ingress bpf obj sample_ret0.o \
        sec .text verbose skip_sw

    Prog section '.text' loaded (5)!
     - Type:         3
     - Instructions: 2 (0 over limit)
     - License:

    Verifier analysis:

    0: (b7) r0 = 0
    1: (95) exit
    [netdevsim] Hello from netdevsim!
    processed 2 insns, stack depth 0

"verbose" flag is required to see it in the console since netdevsim does
not throw an error after printing the message.

Signed-off-by: Quentin Monnet 
Reviewed-by: Jakub Kicinski 
Signed-off-by: David S. Miller

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

2018-01-24T01:24:31+00:00

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 
Reviewed-by: Quentin Monnet 
Signed-off-by: David S. Miller

netdevsim: add extack support for TC eBPF offload

2018-01-24T01:24:31+00:00

Use the recently added extack support for TC eBPF filters in netdevsim.

Signed-off-by: Quentin Monnet 
Reviewed-by: Jakub Kicinski 
Signed-off-by: David S. Miller

netdevsim: bpf: support fake map offload

2018-01-18T21:54:25+00:00

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 
Signed-off-by: Daniel Borkmann