This patch added documentation for BTF (BPF Debug Format).
The document is placed under linux:Documentation/bpf directory.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Quentin Monnet says:

====================
Hi,
This set adds a new command to bpftool in order to dump a list of
eBPF-related parameters for the system (or for a specific network
device) to the console. Once again, this is based on a suggestion from
Daniel.

At this time, output includes:

    - Availability of bpf() system call
    - Availability of bpf() system call for unprivileged users
    - JIT status (enabled or not, with or without debugging traces)
    - JIT hardening status
    - JIT kallsyms exports status
    - Global memory limit for JIT compiler for unprivileged users
    - Status of kernel compilation options related to BPF features
    - Availability of known eBPF program types
    - Availability of known eBPF map types
    - Availability of known eBPF helper functions

There are three different ways to dump this information at this time:

    - Plain output dumps probe results in plain text. It is the most
      flexible options for providing descriptive output to the user, but
      should not be relied upon for parsing the output.
    - JSON output is supported.
    - A third mode, available through the "macros" keyword appended to the
      command line, dumps some of those parameters (not all) as a series of
      "#define" directives, that can be included into a C header file for
      example.

Probes for supported program and map types, and supported helpers, are
directly added to libbpf, so that other applications (or selftests) can
reuse them as necessary.

If the user does not have root privileges (or more precisely, the
CAP_SYS_ADMIN capability) detection will be erroneous for most
parameters. Therefore, forbid non-root users to run the command.

v5:
- Move exported symbols to a new LIBBPF_0.0.2 section in libbpf.map
  (patches 4 to 6).
- Minor fixes on patches 3 and 4.

v4:
- Probe bpf_jit_limit parameter (patch 2).
- Probe some additional kernel config options (patch 3).
- Minor fixes on patch 6.

v3:
- Do not probe kernel version in bpftool (just retrieve it to probe support
  for kprobes in libbpf).
- Change the way results for helper support is displayed: now one list of
  compatible helpers for each program type (and C-style output gets a
  HAVE_PROG_TYPE_HELPER(prog_type, helper) macro to help with tests. See
  patches 6, 7.
- Address other comments from feedback from v2 (please refer to individual
  patches' history).

v2 (please also refer to individual patches' history):
- Move probes for prog/map types, helpers, from bpftool to libbpf.
- Move C-style output as a separate patch, and restrict it to a subset of
  collected information (bpf() availability, prog/map types, helpers).
- Now probe helpers with all supported program types, and display a list of
  compatible program types (as supported on the system) for each helper.
- NOT addressed: grouping compilation options for kernel into subsections
  (patch 3) (I don't see an easy way of grouping them at the moment, please
  see also the discussion on v1 thread).
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Add the bash completion related to the newly introduced "bpftool feature
probe" command.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

bpftool gained support for probing the current system in order to see
what program and map types, and what helpers are available on that
system. This patch adds the possibility to pass an interface index to
libbpf (and hence to the kernel) when trying to load the programs or to
create the maps, in order to see what items a given network device can
support.

A new keyword "dev <ifname>" can be used as an alternative to "kernel"
to indicate that the given device should be tested. If no target ("dev"
or "kernel") is specified bpftool defaults to probing the kernel.

Sample output:

    # bpftool -p feature probe dev lo
    {
        "syscall_config": {
            "have_bpf_syscall": true
        },
        "program_types": {
            "have_sched_cls_prog_type": false,
            "have_xdp_prog_type": false
        },
        ...
    }

As the target is a network device, /proc/ parameters and kernel
configuration are NOT dumped. Availability of the bpf() syscall is
still probed, so we can return early if that syscall is not usable
(since there is no point in attempting the remaining probes in this
case).

Among the program types, only the ones that can be offloaded are probed.
All map types are probed, as there is no specific rule telling which one
could or could not be supported by a device in the future. All helpers
are probed (but only for offload-able program types).

Caveat: as bpftool does not attempt to attach programs to the device at
the moment, probes do not entirely reflect what the device accepts:
typically, for Netronome's nfp, results will announce that TC cls
offload is available even if support has been deactivated (with e.g.
ethtool -K eth1 hw-tc-offload off).

v2:
- All helpers are probed, whereas previous version would only probe the
  ones compatible with an offload-able program type. This is because we
  do not keep a default compatible program type for each helper anymore.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Make bpftool able to dump a subset of the parameters collected by
probing the system as a listing of C-style #define macros, so that
external projects can reuse the result of this probing and build
BPF-based project in accordance with the features available on the
system.

The new "macros" keyword is used to select this output. An additional
"prefix" keyword is added so that users can select a custom prefix for
macro names, in order to avoid any namespace conflict.

Sample output:

    # bpftool feature probe kernel macros prefix FOO_
    /*** System call availability ***/
    #define FOO_HAVE_BPF_SYSCALL

    /*** eBPF program types ***/
    #define FOO_HAVE_SOCKET_FILTER_PROG_TYPE
    #define FOO_HAVE_KPROBE_PROG_TYPE
    #define FOO_HAVE_SCHED_CLS_PROG_TYPE
    ...

    /*** eBPF map types ***/
    #define FOO_HAVE_HASH_MAP_TYPE
    #define FOO_HAVE_ARRAY_MAP_TYPE
    #define FOO_HAVE_PROG_ARRAY_MAP_TYPE
    ...

    /*** eBPF helper functions ***/
    /*
     * Use FOO_HAVE_PROG_TYPE_HELPER(prog_type_name, helper_name)
     * to determine if <helper_name> is available for <prog_type_name>,
     * e.g.
     *      #if FOO_HAVE_PROG_TYPE_HELPER(xdp, bpf_redirect)
     *              // do stuff with this helper
     *      #elif
     *              // use a workaround
     *      #endif
     */
    #define FOO_HAVE_PROG_TYPE_HELPER(prog_type, helper)        \
            FOO_BPF__PROG_TYPE_ ## prog_type ## __HELPER_ ## helper
    ...
    #define FOO_BPF__PROG_TYPE_socket_filter__HELPER_bpf_probe_read 0
    #define FOO_BPF__PROG_TYPE_socket_filter__HELPER_bpf_ktime_get_ns 1
    #define FOO_BPF__PROG_TYPE_socket_filter__HELPER_bpf_trace_printk 1
    ...

v3:
- Change output for helpers again: add a
  HAVE_PROG_TYPE_HELPER(type, helper) macro that can be used to tell
  if <helper> is available for program <type>.

v2:
- #define-based output added as a distinct patch.
- "HAVE_" prefix appended to macro names.
- Output limited to bpf() syscall availability, BPF prog and map types,
  helper functions. In this version kernel config options, procfs
  parameter or kernel version are intentionally left aside.
- Following the change on helper probes, format for helper probes in
  this output style has changed (now a list of compatible program
  types).
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Similarly to what was done for program types and map types, add a set of
probes to test the availability of the different eBPF helper functions
on the current system.

For each known program type, all known helpers are tested, in order to
establish a compatibility matrix. Output is provided as a set of lists
of available helpers, one per program type.

Sample output:

    # bpftool feature probe kernel
    ...
    Scanning eBPF helper functions...
    eBPF helpers supported for program type socket_filter:
            - bpf_map_lookup_elem
            - bpf_map_update_elem
            - bpf_map_delete_elem
    ...
    eBPF helpers supported for program type kprobe:
            - bpf_map_lookup_elem
            - bpf_map_update_elem
            - bpf_map_delete_elem
    ...

    # bpftool --json --pretty feature probe kernel
    {
        ...
        "helpers": {
            "socket_filter_available_helpers": ["bpf_map_lookup_elem", \
                    "bpf_map_update_elem","bpf_map_delete_elem", ...
            ],
            "kprobe_available_helpers": ["bpf_map_lookup_elem", \
                    "bpf_map_update_elem","bpf_map_delete_elem", ...
            ],
            ...
        }
    }

v5:
- In libbpf.map, move global symbol to the new LIBBPF_0.0.2 section.

v4:
- Use "enum bpf_func_id" instead of "__u32" in bpf_probe_helper()
  declaration for the type of the argument used to pass the id of
  the helper to probe.
- Undef BPF_HELPER_MAKE_ENTRY after using it.

v3:
- Do not pass kernel version from bpftool to libbpf probes (kernel
  version for testing program with kprobes is retrieved directly from
  libbpf).
- Dump one list of available helpers per program type (instead of one
  list of compatible program types per helper).

v2:
- Move probes from bpftool to libbpf.
- Test all program types for each helper, print a list of working prog
  types for each helper.
- Fall back on include/uapi/linux/bpf.h for names and ids of helpers.
- Remove C-style macros output from this patch.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Add new probes for eBPF map types, to detect what are the ones available
on the system. Try creating one map of each type, and see if the kernel
complains.

Sample output:

    # bpftool feature probe kernel
    ...
    Scanning eBPF map types...
    eBPF map_type hash is available
    eBPF map_type array is available
    eBPF map_type prog_array is available
    ...

    # bpftool --json --pretty feature probe kernel
    {
        ...
        "map_types": {
            "have_hash_map_type": true,
            "have_array_map_type": true,
            "have_prog_array_map_type": true,
            ...
        }
    }

v5:
- In libbpf.map, move global symbol to the new LIBBPF_0.0.2 section.

v3:
- Use a switch with all enum values for setting specific map parameters,
  so that gcc complains at compile time (-Wswitch-enum) if new map types
  were added to the kernel but libbpf was not updated.

v2:
- Move probes from bpftool to libbpf.
- Remove C-style macros output from this patch.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Introduce probes for supported BPF program types in libbpf, and call it
from bpftool to test what types are available on the system. The probe
simply consists in loading a very basic program of that type and see if
the verifier complains or not.

Sample output:

    # bpftool feature probe kernel
    ...
    Scanning eBPF program types...
    eBPF program_type socket_filter is available
    eBPF program_type kprobe is available
    eBPF program_type sched_cls is available
    ...

    # bpftool --json --pretty feature probe kernel
    {
        ...
        "program_types": {
            "have_socket_filter_prog_type": true,
            "have_kprobe_prog_type": true,
            "have_sched_cls_prog_type": true,
            ...
        }
    }

v5:
- In libbpf.map, move global symbol to a new LIBBPF_0.0.2 section.
- Rename (non-API function) prog_load() as probe_load().

v3:
- Get kernel version for checking kprobes availability from libbpf
  instead of from bpftool. Do not pass kernel_version as an argument
  when calling libbpf probes.
- Use a switch with all enum values for setting specific program
  parameters just before probing, so that gcc complains at compile time
  (-Wswitch-enum) if new prog types were added to the kernel but libbpf
  was not updated.
- Add a comment in libbpf.h about setrlimit() usage to allow many
  consecutive probe attempts.

v2:
- Move probes from bpftool to libbpf.
- Remove C-style macros output from this patch.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Add probes to dump a number of options set (or not set) for compiling
the kernel image. These parameters provide information about what BPF
components should be available on the system. A number of them are not
directly related to eBPF, but are in fact used in the kernel as
conditions on which to compile, or not to compile, some of the eBPF
helper functions.

Sample output:

    # bpftool feature probe kernel
    Scanning system configuration...
    ...
    CONFIG_BPF is set to y
    CONFIG_BPF_SYSCALL is set to y
    CONFIG_HAVE_EBPF_JIT is set to y
    ...

    # bpftool --pretty --json feature probe kernel
    {
        "system_config": {
            ...
            "CONFIG_BPF": "y",
            "CONFIG_BPF_SYSCALL": "y",
            "CONFIG_HAVE_EBPF_JIT": "y",
            ...
        }
    }

v5:
- Declare options[] array in probe_kernel_image_config() as static.

v4:
- Add some options to the list:
    - CONFIG_TRACING
    - CONFIG_KPROBE_EVENTS
    - CONFIG_UPROBE_EVENTS
    - CONFIG_FTRACE_SYSCALLS
- Add comments about those options in the source code.

v3:
- Add a comment about /proc/config.gz not being supported as a path for
  the config file at this time.
- Use p_info() instead of p_err() on failure to get options from config
  file, as bpftool keeps probing other parameters and that would
  possibly create duplicate "error" entries for JSON.

v2:
- Remove C-style macros output from this patch.
- NOT addressed: grouping of those config options into subsections
  (I don't see an easy way of grouping them at the moment, please see
  also the discussion on v1 thread).
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Add a set of probes to dump the eBPF-related parameters available from
/proc/: availability of bpf() syscall for unprivileged users,
JIT compiler status and hardening status, kallsyms exports status.

Sample output:

    # bpftool feature probe kernel
    Scanning system configuration...
    bpf() syscall for unprivileged users is enabled
    JIT compiler is disabled
    JIT compiler hardening is disabled
    JIT compiler kallsyms exports are disabled
    Global memory limit for JIT compiler for unprivileged users \
            is 264241152 bytes
    ...

    # bpftool --json --pretty feature probe kernel
    {
        "system_config": {
            "unprivileged_bpf_disabled": 0,
            "bpf_jit_enable": 0,
            "bpf_jit_harden": 0,
            "bpf_jit_kallsyms": 0,
            "bpf_jit_limit": 264241152
        },
        ...
    }

These probes are skipped if procfs is not mounted.

v4:
- Add bpf_jit_limit parameter.

v2:
- Remove C-style macros output from this patch.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Add a new component and command for bpftool, in order to probe the
system to dump a set of eBPF-related parameters so that users can know
what features are available on the system.

Parameters are dumped in plain or JSON output (with -j/-p options).

The current patch introduces probing of one simple parameter:
availability of the bpf() system call. Later commits
will add other probes.

Sample output:

    # bpftool feature probe kernel
    Scanning system call availability...
    bpf() syscall is available

    # bpftool --json --pretty feature probe kernel
    {
        "syscall_config": {
            "have_bpf_syscall": true
        }
    }

The optional "kernel" keyword enforces probing of the current system,
which is the only possible behaviour at this stage. It can be safely
omitted.

The feature comes with the relevant man page, but bash completion will
come in a dedicated commit.

v3:
- Do not probe kernel version. Contrarily to what is written below for
  v2, we can have the kernel version retrieved in libbpf instead of
  bpftool (in the patch adding probing for program types).

v2:
- Remove C-style macros output from this patch.
- Even though kernel version is no longer needed for testing kprobes
  availability, note that we still collect it in this patch so that
  bpftool gets able to probe (in next patches) older kernels as well.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

An older GCC compiler complains:

kernel/bpf/verifier.c: In function 'bpf_check':
kernel/bpf/verifier.c:4***:13: error: 'prev_offset' may be used uninitialized
      in this function [-Werror=maybe-uninitialized]
   } else if (krecord[i].insn_offset <= prev_offset) {
             ^
kernel/bpf/verifier.c:4***:38: note: 'prev_offset' was declared here
  u32 i, nfuncs, urec_size, min_size, prev_offset;

Although the compiler is wrong here, the patch makes sure
that prev_offset is always initialized, just to silence the warning.

v2: fix a spelling error in the commit message.
Signed-off-by: Peter Oskolkov <posk@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Stanislav Fomichev says:

====================
This patch series add support for queue/stack manipulations.

It goes like this:

   commands by permitting empty keys.

v2:
* removed unneeded jsonw_null from patch #6
* improved bash completions (and moved them into separate patch #7)
====================
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

bpftool map peek id <TAB>      - suggests only queue and stack map ids
bpftool map pop id <TAB>       - suggests only stack map ids
bpftool map dequeue id <TAB>   - suggests only queue map ids

bpftool map push id <TAB>      - suggests only stack map ids
bpftool map enqueue id <TAB>   - suggests only queue map ids

bpftool map push id 1 <TAB>    - suggests 'value', not 'key'
bpftool map enqueue id 2 <TAB> - suggests 'value', not 'key'

bpftool map update id <stack/queue type> - suggests 'value', not 'key'
bpftool map lookup id <stack/queue type> - suggests nothing
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

This is intended to be used with queues and stacks, it pops and prints
the last element via bpf_map_lookup_and_delete_elem.

Example:

bpftool map create /sys/fs/bpf/q type queue value 4 entries 10 name q
bpftool map push pinned /sys/fs/bpf/q value 0 1 2 3
bpftool map pop pinned /sys/fs/bpf/q
value: 00 01 02 03
bpftool map pop pinned /sys/fs/bpf/q
Error: empty map

bpftool map create /sys/fs/bpf/s type stack value 4 entries 10 name s
bpftool map enqueue pinned /sys/fs/bpf/s value 0 1 2 3
bpftool map dequeue pinned /sys/fs/bpf/s
value: 00 01 02 03
bpftool map dequeue pinned /sys/fs/bpf/s
Error: empty map
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

This is intended to be used with queues and stacks and be more
user-friendly than 'update' without the key.

Example:
bpftool map create /sys/fs/bpf/q type queue value 4 entries 10 name q
bpftool map push pinned /sys/fs/bpf/q value 0 1 2 3
bpftool map peek pinned /sys/fs/bpf/q
value: 00 01 02 03

bpftool map create /sys/fs/bpf/s type stack value 4 entries 10 name s
bpftool map enqueue pinned /sys/fs/bpf/s value 0 1 2 3
bpftool map peek pinned /sys/fs/bpf/s
value: 00 01 02 03
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

This is intended to be used with queues and stacks and be more
user-friendly than 'lookup' without key/value.

Example:
bpftool map create /sys/fs/bpf/q type queue value 4 entries 10 name q
bpftool map update pinned /sys/fs/bpf/q value 0 1 2 3
bpftool map peek pinned /sys/fs/bpf/q
value: 00 01 02 03
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

When doing dump or lookup, don't print key if key_size == 0 or value if
value_size == 0. The initial usecase is queue and stack, where we have
only values.

This is for regular output only, json still has all the fields.

Before:
bpftool map create /sys/fs/bpf/q type queue value 4 entries 10 name q
bpftool map update pinned /sys/fs/bpf/q value 0 1 2 3
bpftool map lookup pinned /sys/fs/bpf/q
key:   value: 00 01 02 03

After:
bpftool map create /sys/fs/bpf/q type queue value 4 entries 10 name q
bpftool map update pinned /sys/fs/bpf/q value 0 1 2 3
bpftool map lookup pinned /sys/fs/bpf/q
value: 00 01 02 03
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Bpftool expects key for 'lookup' operations. For some map types, key should
not be specified. Support looking up those map types.

Before:
bpftool map create /sys/fs/bpf/q type queue value 4 entries 10 name q
bpftool map update pinned /sys/fs/bpf/q value 0 1 2 3
bpftool map lookup pinned /sys/fs/bpf/q
Error: did not find key

After:
bpftool map create /sys/fs/bpf/q type queue value 4 entries 10 name q
bpftool map update pinned /sys/fs/bpf/q value 0 1 2 3
bpftool map lookup pinned /sys/fs/bpf/q
key:   value: 00 01 02 03
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Bpftool expects both key and value for 'update' operations. For some
map types, key should not be specified. Support updating those map types.

Before:
bpftool map create /sys/fs/bpf/q type queue value 4 entries 10 name q
bpftool map update pinned /sys/fs/bpf/q value 0 1 2 3
Error: did not find key

After:
bpftool map create /sys/fs/bpf/q type queue value 4 entries 10 name q
bpftool map update pinned /sys/fs/bpf/q value 0 1 2 3
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Yonghong Song says:

====================
Previous maximum supported integer bit width is 64. But
the __int128 type has been supported by most (if not all)
64bit architectures including bpf for both gcc and clang.

The kernel itself uses __int128 for x64 and arm64. Some bcc
tools are using __int128 in bpf programs to describe ipv6
addresses. Without 128bit int support, the vmlinux BTF won't
work and those bpf programs using __int128 cannot utilize BTF.

This patch set therefore implements BTF __int128 support.
====================
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

For formatted output, currently when json is enabled, the decimal
number is required. Similar to kernel bpffs printout,
for int128 numbers, only hex numbers are dumped, which are
quoted as strings.

The below is an example to show plain and json pretty print
based on the map in test_btf pretty print test.

  $ bpftool m s
  75: hash  name pprint_test_has  flags 0x0
        key 4B  value 112B  max_entries 4  memlock 4096B
  $ bpftool m d id 75
  ......
    {
        "key": 3,
        "value": {
            "ui32": 3,
            "ui16": 0,
            "si32": -3,
            "unused_bits2a": 0x3,
            "bits28": 0x3,
            "unused_bits2b": 0x3,
            "": {
                "ui64": 3,
                "ui8a": [3,0,0,0,0,0,0,0
                ]
            },
            "aenum": 3,
            "ui32b": 4,
            "bits2c": 0x1,
            "si128a": 0x3,
            "si128b": 0xfffffffd,
            "bits3": 0x3,
            "bits80": 0x10000000000000003,
            "ui128": 0x20000000000000003
        }
    },
  ......

  $ bptfool -p -j m d id 75
  ......
  {
        "key": ["0x03","0x00","0x00","0x00"
        ],
        "value": ["0x03","0x00","0x00","0x00","0x00","0x00","0x00","0x00",
                  "0xfd","0xff","0xff","0xff","0x0f","0x00","0x00","0xc0",
                  "0x03","0x00","0x00","0x00","0x00","0x00","0x00","0x00",
                  "0x03","0x00","0x00","0x00","0x04","0x00","0x00","0x00",
                  "0x01","0x00","0x00","0x00","0x00","0x00","0x00","0x00",
                  "0x00","0x00","0x00","0x00","0x00","0x00","0x00","0x00",
                  "0x03","0x00","0x00","0x00","0x00","0x00","0x00","0x00",
                  "0x00","0x00","0x00","0x00","0x00","0x00","0x00","0x00",
                  "0xfd","0xff","0xff","0xff","0x00","0x00","0x00","0x00",
                  "0x00","0x00","0x00","0x00","0x00","0x00","0x00","0x00",
                  "0x1b","0x00","0x00","0x00","0x00","0x00","0x00","0x00",
                  "0x08","0x00","0x00","0x00","0x00","0x00","0x00","0x00",
                  "0x03","0x00","0x00","0x00","0x00","0x00","0x00","0x00",
                  "0x02","0x00","0x00","0x00","0x00","0x00","0x00","0x00"
        ],
        "formatted": {
            "key": 3,
            "value": {
                "ui32": 3,
                "ui16": 0,
                "si32": -3,
                "unused_bits2a": "0x3",
                "bits28": "0x3",
                "unused_bits2b": "0x3",
                "": {
                    "ui64": 3,
                    "ui8a": [3,0,0,0,0,0,0,0
                    ]
                },
                "aenum": 3,
                "ui32b": 4,
                "bits2c": "0x1",
                "si128a": "0x3",
                "si128b": "0xfffffffd",
                "bits3": "0x3",
                "bits80": "0x10000000000000003",
                "ui128": "0x20000000000000003"
            }
        }
    }
  ......
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

The bpffs pretty print test is extended to cover int128 types.
Tested on an x64 machine.
  $ test_btf -p
  ......
  BTF pretty print array(#3)......OK
  PASS:9 SKIP:0 FAIL:0
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

The test_btf pretty print is refactored in order to easily
support multiple map value formats. The next patch will
add __int128 type tests which needs macro guard __SIZEOF_INT128__.
There is no functionality change with this patch.
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Several int128 raw type tests are added to test_btf.
Currently these tests are enabled only for x64 and arm64
for which kernel has CONFIG_ARCH_SUPPORTS_INT128 set.

  $ test_btf
  ......
  BTF raw test[106] (128-bit int): OK
  BTF raw test[107] (struct, 128-bit int member): OK
  BTF raw test[108] (struct, 120-bit int member bitfield): OK
  BTF raw test[109] (struct, kind_flag, 128-bit int member): OK
  BTF raw test[110] (struct, kind_flag, 120-bit int member bitfield): OK
  ......
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Currently, btf only supports up to 64-bit integer.
On the other hand, 128bit support for gcc and clang
has existed for a long time. For example, both gcc 4.8
and llvm 3.7 supports types "__int128" and
"unsigned __int128" for virtually all 64bit architectures
including bpf.

The requirement for __int128 support comes from two areas:
  . bpf program may use __int128. For example, some bcc tools
    (https://github.com/iovisor/bcc/tree/master/tools),
    mostly tcp v6 related, tcpstates.py, tcpaccept.py, etc.,
    are using __int128 to represent the ipv6 addresses.
  . linux itself is using __int128 types. Hence supporting
    __int128 type in BTF is required for vmlinux BTF,
    which will be used by "compile once and run everywhere"
    and other projects.

For 128bit integer, instead of base-10, hex numbers are pretty
printed out as large decimal number is hard to decipher, e.g.,
for ipv6 addresses.
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

We are already including tools/scripts/Makefile.include which correctly
handles CROSS_COMPILE, no need to define our own vars.

See related commit 7ed1c190 ("tools: fix cross-compile var clobbering")
for more details.
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Fix over 100 documentation warnings in snmp_counter.rst by
extending the underline string lengths and inserting a blank line
after bullet items.

Examples:

Documentation/networking/snmp_counter.rst:1: WARNING: Title overline too short.
Documentation/networking/snmp_counter.rst:14: WARNING: Bullet list ends without a blank line; unexpected unindent.

Fixes: 2b965472 ("add document for TCP OFO, PAWS and skip ACK counters")
Fixes: 8e2ea53a ("add snmp counters document")
Fixes: 712ee16c ("add documents for snmp counters")
Fixes: 80cc4950 ("net: Add part of TCP counts explanations in snmp_counters.rst")
Fixes: b08794a9 ("documentation of some IP/ICMP snmp counters")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: yupeng <yupeng0921@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

One of the more common cases of allocation size calculations is finding the
size of a structure that has a zero-sized array at the end, along with memory
for some number of elements for that array. For example:

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

instance = kzalloc(sizeof(struct foo) + count * sizeof(struct boo), GFP_KERNEL);

Instead of leaving these open-coded and prone to type mistakes, we can now
use the new struct_size() helper:

instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL);

This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:

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

instance = kzalloc(sizeof(struct foo) + count * sizeof(struct boo), GFP_KERNEL);

Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:

instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL);

This issue was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:

struct foo {
    int stuff;
    void *entry[];
};

instance = kzalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);

Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:

instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL);

This issue was detected with the help of Coccinelle.
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Switch bindings for spi managed mode are using spaces instead of tabs.
Fix them to get a file with a proper kernel indentation style.
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Found by scripts/checkpatch.pl
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Jeff Kirsher says:

====================
100GbE Intel Wired LAN Driver Updates 2019-01-15

This series contains updates to the ice driver only.

Bruce fixes an unused variable build warning, which was introduced with
the commit 2fd527b7 ("net: ndo_bridge_setlink: Add extack").  Added
ethtool support for get_eeprom and get_eeprom_len operations.  Added
support for bringing down the PHY link optional when the interface is
administratively downed.

Anirudh refactors the transmit scheduler functions, which results in
reduced code duplication and adds a helper function, which all the
scheduler functions call instead.  Added an LED blinking handler to
ethtool.  Reworked the queue management code to allow for reuse in
future XDP feature support.  Updates the driver to be able to preserve
the aggregator list after reset by moving it out of port_info and into
ice_hw.  Added the ability to offload SCTP checksum calculation to the
hardware.  Added support for new PHY types, which support higher link
speeds.

Md Fahad makes sure that RSS lookup table and hash key get configured
during the rebuild path after a reset.

Brett updates the driver to set the physical link state according to the
netdev state (up/down).  Added support for adaptive/dynamic interrupt
moderation in the ice driver, along with the ethtool operations needed.

Tony adds software timestamping support by using
ethtool_op_get_ts_info().
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

The function ice_aq_manage_mac_write takes a pointer to a MAC address.
The parameter is not marked const, even though the function doesn't need
to modify it. This prevents passing a parameter that is already marked
const. Update the function prototype to take a const pointer, to allow
passing constant pointers to this function.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch adds code for the detection and operation of several
additional PHY types that support higher link speeds.
Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch adds the ability to offload SCTP checksum calculations to the
NIC.
Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

Use ethtool_op_get_ts_info to provide software timestamping.
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch includes the following ethtool operations:

1. get_coalesce
2. set_coalesce
3. get_per_q_coalesce
4. set_per_q_coalesce

Each ITR value (current_itr/target_itr) are stored on a per
ice_ring_container basis. This is because each valid ice_ring_container
can have 1 or more rings that are tied to the same q_vector ITR index.
Signed-off-by: Brett Creeley <brett.creeley@intel.com>
Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

Currently the driver does not support adaptive/dynamic interrupt
moderation. This patch adds support for this. Also, adaptive/dynamic
interrupt moderation is turned on by default upon driver load.

In order to support adaptive interrupt moderation, two functions were
added, ice_update_itr() and ice_itr_divisor(). These are used to
determine the current packet load and to determine a divisor based
on link speed respectively.

This patch also adds the ICE_ITR_GRAN_S define that is used in the
hot-path when setting a new ITR value. The shift is used to pet two
birds with one hand, set the ITR value while re-enabling the
interrupt. Also, the ICE_ITR_GRAN_S is defined as 1 because the device
has a ITR granularity of 2usecs.
Signed-off-by: Brett Creeley <brett.creeley@intel.com>
Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>