diff options
Diffstat (limited to 'Documentation/bpf')
| -rw-r--r-- | Documentation/bpf/kfuncs.rst | 6 | ||||
| -rw-r--r-- | Documentation/bpf/libbpf/program_types.rst | 10 | ||||
| -rw-r--r-- | Documentation/bpf/prog_flow_dissector.rst | 2 | ||||
| -rw-r--r-- | Documentation/bpf/standardization/instruction-set.rst | 8 |
4 files changed, 21 insertions, 5 deletions
diff --git a/Documentation/bpf/kfuncs.rst b/Documentation/bpf/kfuncs.rst index 0d2647fb35..723408e399 100644 --- a/Documentation/bpf/kfuncs.rst +++ b/Documentation/bpf/kfuncs.rst @@ -37,16 +37,14 @@ prototype in a header for the wrapper kfunc. An example is given below:: /* Disables missing prototype warnings */ - __diag_push(); - __diag_ignore_all("-Wmissing-prototypes", - "Global kfuncs as their definitions will be in BTF"); + __bpf_kfunc_start_defs(); __bpf_kfunc struct task_struct *bpf_find_get_task_by_vpid(pid_t nr) { return find_get_task_by_vpid(nr); } - __diag_pop(); + __bpf_kfunc_end_defs(); A wrapper kfunc is often needed when we need to annotate parameters of the kfunc. Otherwise one may directly make the kfunc visible to the BPF program by diff --git a/Documentation/bpf/libbpf/program_types.rst b/Documentation/bpf/libbpf/program_types.rst index ad4d4d5eec..63bb88846e 100644 --- a/Documentation/bpf/libbpf/program_types.rst +++ b/Documentation/bpf/libbpf/program_types.rst @@ -56,6 +56,16 @@ described in more detail in the footnotes. | | ``BPF_CGROUP_UDP6_RECVMSG`` | ``cgroup/recvmsg6`` | | + +----------------------------------------+----------------------------------+-----------+ | | ``BPF_CGROUP_UDP6_SENDMSG`` | ``cgroup/sendmsg6`` | | +| +----------------------------------------+----------------------------------+-----------+ +| | ``BPF_CGROUP_UNIX_CONNECT`` | ``cgroup/connect_unix`` | | +| +----------------------------------------+----------------------------------+-----------+ +| | ``BPF_CGROUP_UNIX_SENDMSG`` | ``cgroup/sendmsg_unix`` | | +| +----------------------------------------+----------------------------------+-----------+ +| | ``BPF_CGROUP_UNIX_RECVMSG`` | ``cgroup/recvmsg_unix`` | | +| +----------------------------------------+----------------------------------+-----------+ +| | ``BPF_CGROUP_UNIX_GETPEERNAME`` | ``cgroup/getpeername_unix`` | | +| +----------------------------------------+----------------------------------+-----------+ +| | ``BPF_CGROUP_UNIX_GETSOCKNAME`` | ``cgroup/getsockname_unix`` | | +-------------------------------------------+----------------------------------------+----------------------------------+-----------+ | ``BPF_PROG_TYPE_CGROUP_SOCK`` | ``BPF_CGROUP_INET4_POST_BIND`` | ``cgroup/post_bind4`` | | + +----------------------------------------+----------------------------------+-----------+ diff --git a/Documentation/bpf/prog_flow_dissector.rst b/Documentation/bpf/prog_flow_dissector.rst index 4d86780ab0..f24270b8b0 100644 --- a/Documentation/bpf/prog_flow_dissector.rst +++ b/Documentation/bpf/prog_flow_dissector.rst @@ -113,7 +113,7 @@ Flags used by ``eth_get_headlen`` to estimate length of all headers for GRO. * ``BPF_FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL`` - tells BPF flow dissector to stop parsing as soon as it reaches IPv6 flow label; used by - ``___skb_get_hash`` and ``__skb_get_hash_symmetric`` to get flow hash. + ``___skb_get_hash`` to get flow hash. * ``BPF_FLOW_DISSECTOR_F_STOP_AT_ENCAP`` - tells BPF flow dissector to stop parsing as soon as it reaches encapsulated headers; used by routing infrastructure. diff --git a/Documentation/bpf/standardization/instruction-set.rst b/Documentation/bpf/standardization/instruction-set.rst index c5d53a6e8c..245b6defc2 100644 --- a/Documentation/bpf/standardization/instruction-set.rst +++ b/Documentation/bpf/standardization/instruction-set.rst @@ -283,6 +283,14 @@ For signed operations (``BPF_SDIV`` and ``BPF_SMOD``), for ``BPF_ALU``, is first :term:`sign extended<Sign Extend>` from 32 to 64 bits, and then interpreted as a 64-bit signed value. +Note that there are varying definitions of the signed modulo operation +when the dividend or divisor are negative, where implementations often +vary by language such that Python, Ruby, etc. differ from C, Go, Java, +etc. This specification requires that signed modulo use truncated division +(where -13 % 3 == -1) as implemented in C, Go, etc.: + + a % n = a - n * trunc(a / n) + The ``BPF_MOVSX`` instruction does a move operation with sign extension. ``BPF_ALU | BPF_MOVSX`` :term:`sign extends<Sign Extend>` 8-bit and 16-bit operands into 32 bit operands, and zeroes the remaining upper 32 bits. |