Commit Graph

118 Commits

Author SHA1 Message Date
Paul E. McKenney 8fcf19696a bpf: Update bpf_design_QA.rst to clarify that BTF_ID does not ABIify a function
This patch updates bpf_design_QA.rst to clarify that mentioning a function
to the BTF_ID macro does not make that function become part of the Linux
kernel's ABI.

Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/20220802173913.4170192-3-paulmck@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-08-04 13:17:24 -07:00
Paul E. McKenney 62fc770d90 bpf: Update bpf_design_QA.rst to clarify that attaching to functions is not ABI
This patch updates bpf_design_QA.rst to clarify that the ability to
attach a BPF program to an arbitrary function in the kernel does not
make that function become part of the Linux kernel's ABI.

[ paulmck: Apply Daniel Borkmann feedback. ]

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/20220802173913.4170192-2-paulmck@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-08-04 13:17:24 -07:00
Paul E. McKenney b9b738eeaf bpf: Update bpf_design_QA.rst to clarify that kprobes is not ABI
This patch updates bpf_design_QA.rst to clarify that the ability to
attach a BPF program to a given point in the kernel code via kprobes
does not make that attachment point be part of the Linux kernel's ABI.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/20220802173913.4170192-1-paulmck@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-08-04 13:17:24 -07:00
Kumar Kartikeya Dwivedi 63e564ebd1 bpf: Add documentation for kfuncs
As the usage of kfuncs grows, we are starting to form consensus on the
kinds of attributes and annotations that kfuncs can have. To better help
developers make sense of the various options available at their disposal
to present an unstable API to the BPF users, document the various kfunc
flags and annotations, their expected usage, and explain the process of
defining and registering a kfunc set.

Cc: KP Singh <kpsingh@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20220721134245.2450-6-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-07-21 21:03:16 -07:00
Donald Hunter 979855d302 bpf, docs: document BPF_MAP_TYPE_HASH and variants
Add documentation for BPF_MAP_TYPE_HASH including kernel version
introduced, usage and examples. Document BPF_MAP_TYPE_PERCPU_HASH,
BPF_MAP_TYPE_LRU_HASH and BPF_MAP_TYPE_LRU_PERCPU_HASH variations.

Note that this file is included in the BPF documentation by the glob in
Documentation/bpf/maps.rst

v3:
Fix typos reported by Stanislav Fomichev and Yonghong Song.
Add note about iteration and deletion as requested by Yonghong Song.

v2:
Describe memory allocation semantics as suggested by Stanislav Fomichev.
Fix u64 typo reported by Stanislav Fomichev.
Cut down usage examples to only show usage in context.
Updated patch description to follow style recommendation, reported by
Bagas Sanjaya.

Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20220718125847.1390-1-donald.hunter@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-07-19 10:38:03 -07:00
Indu Bhagat e5e23424e5 docs/bpf: Update documentation for BTF_KIND_FUNC
The vlen bits in the BTF type of kind BTF_KIND_FUNC are used to convey the
linkage information for functions. The Linux kernel only supports
linkage values of BTF_FUNC_STATIC and BTF_FUNC_GLOBAL at this time.

Signed-off-by: Indu Bhagat <indu.bhagat@oracle.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/r/20220714223310.1140097-1-indu.bhagat@oracle.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-07-19 09:42:09 -07:00
Pu Lehui fb8ddf24c7 bpf, docs: Remove deprecated xsk libbpf APIs description
Since xsk APIs has been removed from libbpf, let's clean up the
BPF docs simutaneously.

Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/bpf/20220708042736.669132-1-pulehui@huawei.com
2022-07-08 14:18:50 +02:00
Shahab Vahedi 2f6d1e0f8f bpf, docs: Fix the code formatting in instruction-set
A minor typo fix to include "| BPF_LD" into its previous
code phrase:

``BPF_IND`` | BPF_LD --> ``BPF_IND | BPF_LD``

Signed-off-by: Shahab Vahedi <shahab@synopsys.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/b6120b31-3d1d-bf2d-2f2a-aa768d91257b@synopsys.com
2022-06-24 13:58:32 -07:00
Kosuke Fujimoto 492f99e419 bpf, docs: Fix typo "BFP_ALU" to "BPF_ALU"
"BFP" should be "BPF"

Signed-off-by: Kosuke Fujimoto <fujimotokosuke0@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220609083937.245749-1-fujimotoksouke0@gmail.com
2022-06-09 14:06:41 +02:00
Yonghong Song 61dbd59829 docs/bpf: Update documentation for BTF_KIND_ENUM64 support
Add BTF_KIND_ENUM64 documentation in btf.rst.
Also fixed a typo for section number for BTF_KIND_TYPE_TAG
from 2.2.17 to 2.2.18, and fixed a type size issue for
BTF_KIND_ENUM.

Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20220607062724.3728215-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-07 10:20:44 -07:00
Tiezhu Yang 9a9a90ca13 bpf, docs: Fix typo "respetively" to "respectively"
"respetively" should be "respectively".

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/1651139754-4838-4-git-send-email-yangtiezhu@loongson.cn
2022-04-28 17:20:48 +02:00
Tiezhu Yang c821d80bb8 bpf, docs: BPF_FROM_BE exists as alias for BPF_TO_BE
According to include/uapi/linux/bpf.h:

  #define BPF_FROM_LE	BPF_TO_LE
  #define BPF_FROM_BE	BPF_TO_BE

BPF_FROM_BE exists as alias for BPF_TO_BE instead of BPF_TO_LE.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/1651139754-4838-3-git-send-email-yangtiezhu@loongson.cn
2022-04-28 17:20:48 +02:00
Tiezhu Yang 67b97e5842 bpf, docs: Remove duplicated word "instructions"
The word "instructions" is duplicated, remove it.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/1651139754-4838-2-git-send-email-yangtiezhu@loongson.cn
2022-04-28 17:20:48 +02:00
Grant Seltzer e8c5e1a0f7 libbpf: Improve libbpf API documentation link position
This puts the link for libbpf API documentation into the sidebar
for much easier navigation.

You can preview this change at:

  https://libbpf-test.readthedocs.io/en/latest/

Note that the link is hardcoded to the production version, so you
can see that it self references itself here for now:

  https://libbpf-test.readthedocs.io/en/latest/api.html

This will need to make its way into the libbpf mirror, before being
deployed to libbpf.readthedocs.org

Signed-off-by: Grant Seltzer <grantseltzer@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220422031050.303984-1-grantseltzer@gmail.com
2022-04-22 16:21:56 +02:00
Jakub Kicinski 8df0136376 docs: netdev: move the netdev-FAQ to the process pages
The documentation for the tip tree is really in quite a similar
spirit to the netdev-FAQ. Move the netdev-FAQ to the process docs
as well.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-03-31 10:49:39 +02:00
Toke Høiland-Jørgensen 1a7551f150 Documentation/bpf: Add documentation for BPF_PROG_RUN
This adds documentation for the BPF_PROG_RUN command; a short overview of
the command itself, and a more verbose description of the "live packet"
mode for XDP introduced in the previous commit.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20220309105346.100053-3-toke@redhat.com
2022-03-09 14:19:22 -08:00
Wan Jiabing 43429ea74a bpf, docs: Add a missing colon in verifier.rst
Add a missing colon to fix the document style.

Fixes: 88691e9e1e ("bpf, docs: Split general purpose eBPF documentation out of filter.rst")
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220228080416.1689327-1-wanjiabing@vivo.com
2022-02-28 18:20:35 +01:00
Christoph Hellwig 594d323485 bpf, docs: Better document the atomic instructions
Use proper tables and RST markup to document the atomic instructions
in a structured way.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220131183638.3934982-6-hch@lst.de
2022-02-03 09:29:37 -08:00
Christoph Hellwig 5ca15b8a93 bpf, docs: Better document the extended instruction format
In addition to the normal 64-bit instruction encoding, eBPF also has
a single instruction that uses a second 64-bit bits for a second
immediate value.  Instead of only documenting this format deep down
in the document mention it in the instruction encoding section.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220131183638.3934982-5-hch@lst.de
2022-02-03 09:29:37 -08:00
Christoph Hellwig 1517533627 bpf, docs: Better document the legacy packet access instruction
Use consistent terminology and structured RST elements to better document
these two oddball instructions.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220131183638.3934982-4-hch@lst.de
2022-02-03 09:29:31 -08:00
Christoph Hellwig 63d8c242b9 bpf, docs: Better document the regular load and store instructions
Add a separate section and a little intro blurb for the regular load and
store instructions.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220131183638.3934982-3-hch@lst.de
2022-02-03 09:23:09 -08:00
Christoph Hellwig dd33fb571f bpf, docs: Document the byte swapping instructions
Add a section to document the byte swapping instructions.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220131183638.3934982-2-hch@lst.de
2022-02-03 09:23:09 -08:00
Yonghong Song b72903847a docs/bpf: clarify how btf_type_tag gets encoded in the type chain
Clarify where the BTF_KIND_TYPE_TAG gets encoded in the type chain,
so applications and kernel can properly parse them.

Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20220127154627.665163-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-27 12:03:47 -08:00
Andrii Nakryiko 96c85308ee docs/bpf: update BPF map definition example
Use BTF-defined map definition in the documentation example.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220120060529.1890907-5-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-20 21:19:05 -08:00
Christoph Hellwig 58d8a3fc4a bpf, docs: Fully document the JMP mode modifiers
Add a description for all the modifiers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220103183556.41040-7-hch@lst.de
2022-01-05 13:11:26 -08:00
Christoph Hellwig 9e533e22b5 bpf, docs: Fully document the JMP opcodes
Add pseudo-code to document all the different BPF_JMP / BPF_JMP64
opcodes.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220103183556.41040-6-hch@lst.de
2022-01-05 13:11:26 -08:00
Christoph Hellwig 03c517ee9e bpf, docs: Fully document the ALU opcodes
Add pseudo-code to document all the different BPF_ALU / BPF_ALU64
opcodes.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220103183556.41040-5-hch@lst.de
2022-01-05 13:11:26 -08:00
Christoph Hellwig 894cda554c bpf, docs: Document the opcode classes
Add a description for each opcode class.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220103183556.41040-4-hch@lst.de
2022-01-05 13:11:26 -08:00
Christoph Hellwig be3193cded bpf, docs: Add subsections for ALU and JMP instructions
Add a little more stucture to the ALU/JMP documentation with sections and
improve the example text.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220103183556.41040-3-hch@lst.de
2022-01-05 13:11:26 -08:00
Christoph Hellwig 62e4683849 bpf, docs: Add a setion to explain the basic instruction encoding
The eBPF instruction set document does not currently document the basic
instruction encoding.  Add a section to do that.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220103183556.41040-2-hch@lst.de
2022-01-05 13:11:26 -08:00
Christoph Hellwig 63d000c3dc bpf, docs: Move the packet access instructions last in instruction-set.rst
The packet access instructions are a convoluted leftover from classic
BPF.  Move them last past the much more important atomic operations,
and improve the rendering of the code example.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211223101906.977624-5-hch@lst.de
2021-12-30 16:34:03 -08:00
Christoph Hellwig 5e4dd19f00 bpf, docs: Generate nicer tables for instruction encodings
Use RST tables that are nicely readable both in plain ascii as well as
in html to render the instruction encodings, and add a few subheadings
to better structure the text.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211223101906.977624-4-hch@lst.de
2021-12-30 16:33:57 -08:00
Christoph Hellwig 41db511a3a bpf, docs: Split the comparism to classic BPF from instruction-set.rst
Split the introductory that explain eBPF vs classic BPF and how it maps
to hardware from the instruction set specification into a standalone
document.  This duplicates a little bit of information but gives us a
useful reference for the eBPF instrution set that is not encumbered by
classic BPF.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211223101906.977624-3-hch@lst.de
2021-12-30 16:31:44 -08:00
Christoph Hellwig fa86aa77d4 bpf, docs: Fix verifier references
Use normal RST file reference instead of linkage copied from the old filter.rst
document that does not actually work when using HTML output.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211223101906.977624-2-hch@lst.de
2021-12-30 16:31:44 -08:00
Christoph Hellwig 88691e9e1e bpf, docs: Split general purpose eBPF documentation out of filter.rst
filter.rst starts out documenting the classic BPF and then spills into
introducing and documentating eBPF.  Move the eBPF documentation into
rwo new files under Documentation/bpf/ for the instruction set and
the verifier and link to the BPF documentation from filter.rst.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20211119163215.971383-6-hch@lst.de
2021-11-30 10:52:11 -08:00
Christoph Hellwig bc84e959e5 bpf, docs: Move handling of maps to Documentation/bpf/maps.rst
Move the general maps documentation into the maps.rst file from the
overall networking filter documentation and add a link instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20211119163215.971383-5-hch@lst.de
2021-11-30 10:52:11 -08:00
Dave Tucker 5931d9a3d0 bpf, docs: Fix ordering of bpf documentation
This commit fixes the display of the BPF documentation in the sidebar
when rendered as HTML.

Before this patch, the sidebar would render as follows for some
sections:

| BPF Documentation
  |- BPF Type Format (BTF)
    |- BPF Type Format (BTF)

This was due to creating a heading in index.rst followed by
a sphinx toctree, where the file referenced carries the same
title as the section heading.

To fix this I applied a pattern that has been established in other
subfolders of Documentation:

1. Re-wrote index.rst to have a single toctree
2. Split the sections out in to their own files

Additionally maps.rst and programs.rst make use of a glob pattern to
include map_* or prog_* rst files in their toctree, meaning future map
or program type documentation will be automatically included.

Signed-off-by: Dave Tucker <dave@dtucker.co.uk>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/1a1eed800e7b9dc13b458de113a489641519b0cc.1636749493.git.dave@dtucker.co.uk
2021-11-17 23:24:01 +01:00
Dave Tucker f5b1c2ef43 bpf, docs: Rename bpf_lsm.rst to prog_lsm.rst
This allows for documentation relating to BPF Program Types to be
matched by the glob pattern prog_* for inclusion in a sphinx toctree

Signed-off-by: Dave Tucker <dave@dtucker.co.uk>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: KP Singh <kpsingh@kernel.org>
Link: https://lore.kernel.org/bpf/49fe0f370a2b28500c1b60f1fdb6fb7ec90de28a.1636749493.git.dave@dtucker.co.uk
2021-11-17 23:23:58 +01:00
Dave Tucker 3ff36bffaf bpf, docs: Change underline in btf to match style guide
This changes the type of underline used to follow the guidelines in
Documentation/doc-guide/sphinx.rst which also ensures that the headings
are rendered at the correct level in the HTML sidebar

Signed-off-by: Dave Tucker <dave@dtucker.co.uk>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/981b27485cc294206480df36fca46817e2553e39.1636749493.git.dave@dtucker.co.uk
2021-11-17 23:23:52 +01:00
Yonghong Song d52f5c639d docs/bpf: Update documentation for BTF_KIND_TYPE_TAG support
Add BTF_KIND_TYPE_TAG documentation in btf.rst.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211112012656.1509082-1-yhs@fb.com
2021-11-11 17:41:11 -08:00
Yonghong Song 5a8671349d docs/bpf: Update documentation for BTF_KIND_DECL_TAG typedef support
Add BTF_KIND_DECL_TAG typedef support in btf.rst.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211021195649.4020514-1-yhs@fb.com
2021-10-22 17:04:44 -07:00
Yonghong Song 223f903e9c bpf: Rename BTF_KIND_TAG to BTF_KIND_DECL_TAG
Patch set [1] introduced BTF_KIND_TAG to allow tagging
declarations for struct/union, struct/union field, var, func
and func arguments and these tags will be encoded into
dwarf. They are also encoded to btf by llvm for the bpf target.

After BTF_KIND_TAG is introduced, we intended to use it
for kernel __user attributes. But kernel __user is actually
a type attribute. Upstream and internal discussion showed
it is not a good idea to mix declaration attribute and
type attribute. So we proposed to introduce btf_type_tag
as a type attribute and existing btf_tag renamed to
btf_decl_tag ([2]).

This patch renamed BTF_KIND_TAG to BTF_KIND_DECL_TAG and some
other declarations with *_tag to *_decl_tag to make it clear
the tag is for declaration. In the future, BTF_KIND_TYPE_TAG
might be introduced per [3].

 [1] https://lore.kernel.org/bpf/20210914223004.244411-1-yhs@fb.com/
 [2] https://reviews.llvm.org/D111588
 [3] https://reviews.llvm.org/D111199

Fixes: b5ea834dde ("bpf: Support for new btf kind BTF_KIND_TAG")
Fixes: 5b84bd1036 ("libbpf: Add support for BTF_KIND_TAG")
Fixes: 5c07f2fec0 ("bpftool: Add support for BTF_KIND_TAG")
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211012164838.3345699-1-yhs@fb.com
2021-10-18 18:35:36 -07:00
Grant Seltzer 9330303446 libbpf: Add API documentation convention guidelines
This adds a section to the documentation for libbpf
naming convention which describes how to document
API features in libbpf, specifically the format of
which API doc comments need to conform to.

Signed-off-by: Grant Seltzer <grantseltzer@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20211004215644.497327-1-grantseltzer@gmail.com
2021-10-06 12:34:02 -07:00
Alexei Starovoitov c86216bc96 bpf: Document BPF licensing.
Document and clarify BPF licensing.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Joe Stringer <joe@cilium.io>
Acked-by: Lorenz Bauer <lmb@cloudflare.com>
Acked-by: Dave Thaler <dthaler@microsoft.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: KP Singh <kpsingh@kernel.org>
Link: https://lore.kernel.org/bpf/20210917230034.51080-1-alexei.starovoitov@gmail.com
2021-09-22 23:13:13 +02:00
Yonghong Song 48f5a6c416 docs/bpf: Add documentation for BTF_KIND_TAG
Add BTF_KIND_TAG documentation in btf.rst.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210914223103.249100-1-yhs@fb.com
2021-09-14 18:45:53 -07:00
Grant Seltzer d20b41115a libbpf: Rename libbpf documentation index file
This patch renames a documentation libbpf.rst to index.rst. In order
for readthedocs.org to pick this file up and properly build the
documentation site.

It also changes the title type of the ABI subsection in the
naming convention doc. This is so that readthedocs.org doesn't treat this
section as a separate document.

Signed-off-by: Grant Seltzer <grantseltzer@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210818151313.49992-1-grantseltzer@gmail.com
2021-08-18 08:45:25 -07:00
grantseltzer bb57164920 bpf: Reconfigure libbpf docs to remove unversioned API
This removes the libbpf_api.rst file from the kernel documentation.
The intention for this file was to pull documentation from comments
above API functions in libbpf. However, due to limitations of the
kernel documentation system, this API documentation could not be
versioned, which is counterintuative to how users expect to use it.
There is also currently no doc comments, making this a blank page.

Once the kernel comment documentation is actually contributed, it
will still exist in the kernel repository, just in the code itself.

A seperate site is being spun up to generate documentaiton from those
comments in a way in which it can be versioned properly.

This also reconfigures the bpf documentation index page to make it
easier to sync to the previously mentioned documentaiton site.

Signed-off-by: Grant Seltzer <grantseltzer@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210810020508.280639-1-grantseltzer@gmail.com
2021-08-16 17:25:03 -07:00
Randy Dunlap 7c4a22339e libbpf, doc: Eliminate warnings in libbpf_naming_convention
Use "code-block: none" instead of "c" for non-C-language code blocks.
Removes these warnings:

  lnx-514-rc4/Documentation/bpf/libbpf/libbpf_naming_convention.rst:111: WARNING: Could not lex literal_block as "c". Highlighting skipped.
  lnx-514-rc4/Documentation/bpf/libbpf/libbpf_naming_convention.rst:124: WARNING: Could not lex literal_block as "c". Highlighting skipped.

Fixes: f42cfb469f ("bpf: Add documentation for libbpf including API autogen")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210802015037.787-1-rdunlap@infradead.org
2021-08-07 01:39:19 +02:00
Linus Torvalds dbe69e4337 Networking changes for 5.14.
Core:
 
  - BPF:
    - add syscall program type and libbpf support for generating
      instructions and bindings for in-kernel BPF loaders (BPF loaders
      for BPF), this is a stepping stone for signed BPF programs
    - infrastructure to migrate TCP child sockets from one listener
      to another in the same reuseport group/map to improve flexibility
      of service hand-off/restart
    - add broadcast support to XDP redirect
 
  - allow bypass of the lockless qdisc to improving performance
    (for pktgen: +23% with one thread, +44% with 2 threads)
 
  - add a simpler version of "DO_ONCE()" which does not require
    jump labels, intended for slow-path usage
 
  - virtio/vsock: introduce SOCK_SEQPACKET support
 
  - add getsocketopt to retrieve netns cookie
 
  - ip: treat lowest address of a IPv4 subnet as ordinary unicast address
        allowing reclaiming of precious IPv4 addresses
 
  - ipv6: use prandom_u32() for ID generation
 
  - ip: add support for more flexible field selection for hashing
        across multi-path routes (w/ offload to mlxsw)
 
  - icmp: add support for extended RFC 8335 PROBE (ping)
 
  - seg6: add support for SRv6 End.DT46 behavior
 
  - mptcp:
     - DSS checksum support (RFC 8684) to detect middlebox meddling
     - support Connection-time 'C' flag
     - time stamping support
 
  - sctp: packetization Layer Path MTU Discovery (RFC 8899)
 
  - xfrm: speed up state addition with seq set
 
  - WiFi:
     - hidden AP discovery on 6 GHz and other HE 6 GHz improvements
     - aggregation handling improvements for some drivers
     - minstrel improvements for no-ack frames
     - deferred rate control for TXQs to improve reaction times
     - switch from round robin to virtual time-based airtime scheduler
 
  - add trace points:
     - tcp checksum errors
     - openvswitch - action execution, upcalls
     - socket errors via sk_error_report
 
 Device APIs:
 
  - devlink: add rate API for hierarchical control of max egress rate
             of virtual devices (VFs, SFs etc.)
 
  - don't require RCU read lock to be held around BPF hooks
    in NAPI context
 
  - page_pool: generic buffer recycling
 
 New hardware/drivers:
 
  - mobile:
     - iosm: PCIe Driver for Intel M.2 Modem
     - support for Qualcomm MSM8998 (ipa)
 
  - WiFi: Qualcomm QCN9074 and WCN6855 PCI devices
 
  - sparx5: Microchip SparX-5 family of Enterprise Ethernet switches
 
  - Mellanox BlueField Gigabit Ethernet (control NIC of the DPU)
 
  - NXP SJA1110 Automotive Ethernet 10-port switch
 
  - Qualcomm QCA8327 switch support (qca8k)
 
  - Mikrotik 10/25G NIC (atl1c)
 
 Driver changes:
 
  - ACPI support for some MDIO, MAC and PHY devices from Marvell and NXP
    (our first foray into MAC/PHY description via ACPI)
 
  - HW timestamping (PTP) support: bnxt_en, ice, sja1105, hns3, tja11xx
 
  - Mellanox/Nvidia NIC (mlx5)
    - NIC VF offload of L2 bridging
    - support IRQ distribution to Sub-functions
 
  - Marvell (prestera):
     - add flower and match all
     - devlink trap
     - link aggregation
 
  - Netronome (nfp): connection tracking offload
 
  - Intel 1GE (igc): add AF_XDP support
 
  - Marvell DPU (octeontx2): ingress ratelimit offload
 
  - Google vNIC (gve): new ring/descriptor format support
 
  - Qualcomm mobile (rmnet & ipa): inline checksum offload support
 
  - MediaTek WiFi (mt76)
     - mt7915 MSI support
     - mt7915 Tx status reporting
     - mt7915 thermal sensors support
     - mt7921 decapsulation offload
     - mt7921 enable runtime pm and deep sleep
 
  - Realtek WiFi (rtw88)
     - beacon filter support
     - Tx antenna path diversity support
     - firmware crash information via devcoredump
 
  - Qualcomm 60GHz WiFi (wcn36xx)
     - Wake-on-WLAN support with magic packets and GTK rekeying
 
  - Micrel PHY (ksz886x/ksz8081): add cable test support
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-next-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Pull networking updates from Jakub Kicinski:
 "Core:

   - BPF:
      - add syscall program type and libbpf support for generating
        instructions and bindings for in-kernel BPF loaders (BPF loaders
        for BPF), this is a stepping stone for signed BPF programs
      - infrastructure to migrate TCP child sockets from one listener to
        another in the same reuseport group/map to improve flexibility
        of service hand-off/restart
      - add broadcast support to XDP redirect

   - allow bypass of the lockless qdisc to improving performance (for
     pktgen: +23% with one thread, +44% with 2 threads)

   - add a simpler version of "DO_ONCE()" which does not require jump
     labels, intended for slow-path usage

   - virtio/vsock: introduce SOCK_SEQPACKET support

   - add getsocketopt to retrieve netns cookie

   - ip: treat lowest address of a IPv4 subnet as ordinary unicast
     address allowing reclaiming of precious IPv4 addresses

   - ipv6: use prandom_u32() for ID generation

   - ip: add support for more flexible field selection for hashing
     across multi-path routes (w/ offload to mlxsw)

   - icmp: add support for extended RFC 8335 PROBE (ping)

   - seg6: add support for SRv6 End.DT46 behavior

   - mptcp:
      - DSS checksum support (RFC 8684) to detect middlebox meddling
      - support Connection-time 'C' flag
      - time stamping support

   - sctp: packetization Layer Path MTU Discovery (RFC 8899)

   - xfrm: speed up state addition with seq set

   - WiFi:
      - hidden AP discovery on 6 GHz and other HE 6 GHz improvements
      - aggregation handling improvements for some drivers
      - minstrel improvements for no-ack frames
      - deferred rate control for TXQs to improve reaction times
      - switch from round robin to virtual time-based airtime scheduler

   - add trace points:
      - tcp checksum errors
      - openvswitch - action execution, upcalls
      - socket errors via sk_error_report

  Device APIs:

   - devlink: add rate API for hierarchical control of max egress rate
     of virtual devices (VFs, SFs etc.)

   - don't require RCU read lock to be held around BPF hooks in NAPI
     context

   - page_pool: generic buffer recycling

  New hardware/drivers:

   - mobile:
      - iosm: PCIe Driver for Intel M.2 Modem
      - support for Qualcomm MSM8998 (ipa)

   - WiFi: Qualcomm QCN9074 and WCN6855 PCI devices

   - sparx5: Microchip SparX-5 family of Enterprise Ethernet switches

   - Mellanox BlueField Gigabit Ethernet (control NIC of the DPU)

   - NXP SJA1110 Automotive Ethernet 10-port switch

   - Qualcomm QCA8327 switch support (qca8k)

   - Mikrotik 10/25G NIC (atl1c)

  Driver changes:

   - ACPI support for some MDIO, MAC and PHY devices from Marvell and
     NXP (our first foray into MAC/PHY description via ACPI)

   - HW timestamping (PTP) support: bnxt_en, ice, sja1105, hns3, tja11xx

   - Mellanox/Nvidia NIC (mlx5)
      - NIC VF offload of L2 bridging
      - support IRQ distribution to Sub-functions

   - Marvell (prestera):
      - add flower and match all
      - devlink trap
      - link aggregation

   - Netronome (nfp): connection tracking offload

   - Intel 1GE (igc): add AF_XDP support

   - Marvell DPU (octeontx2): ingress ratelimit offload

   - Google vNIC (gve): new ring/descriptor format support

   - Qualcomm mobile (rmnet & ipa): inline checksum offload support

   - MediaTek WiFi (mt76)
      - mt7915 MSI support
      - mt7915 Tx status reporting
      - mt7915 thermal sensors support
      - mt7921 decapsulation offload
      - mt7921 enable runtime pm and deep sleep

   - Realtek WiFi (rtw88)
      - beacon filter support
      - Tx antenna path diversity support
      - firmware crash information via devcoredump

   - Qualcomm WiFi (wcn36xx)
      - Wake-on-WLAN support with magic packets and GTK rekeying

   - Micrel PHY (ksz886x/ksz8081): add cable test support"

* tag 'net-next-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2168 commits)
  tcp: change ICSK_CA_PRIV_SIZE definition
  tcp_yeah: check struct yeah size at compile time
  gve: DQO: Fix off by one in gve_rx_dqo()
  stmmac: intel: set PCI_D3hot in suspend
  stmmac: intel: Enable PHY WOL option in EHL
  net: stmmac: option to enable PHY WOL with PMT enabled
  net: say "local" instead of "static" addresses in ndo_dflt_fdb_{add,del}
  net: use netdev_info in ndo_dflt_fdb_{add,del}
  ptp: Set lookup cookie when creating a PTP PPS source.
  net: sock: add trace for socket errors
  net: sock: introduce sk_error_report
  net: dsa: replay the local bridge FDB entries pointing to the bridge dev too
  net: dsa: ensure during dsa_fdb_offload_notify that dev_hold and dev_put are on the same dev
  net: dsa: include fdb entries pointing to bridge in the host fdb list
  net: dsa: include bridge addresses which are local in the host fdb list
  net: dsa: sync static FDB entries on foreign interfaces to hardware
  net: dsa: install the host MDB and FDB entries in the master's RX filter
  net: dsa: reference count the FDB addresses at the cross-chip notifier level
  net: dsa: introduce a separate cross-chip notifier type for host FDBs
  net: dsa: reference count the MDB entries at the cross-chip notifier level
  ...
2021-06-30 15:51:09 -07:00
Grant Seltzer f42cfb469f bpf: Add documentation for libbpf including API autogen
This patch is meant to start the initiative to document libbpf.
It includes .rst files which are text documentation describing building,
API naming convention, as well as an index to generated API documentation.

In this approach the generated API documentation is enabled by the kernels
existing kernel documentation system which uses sphinx. The resulting docs
would then be synced to kernel.org/doc

You can test this by running `make htmldocs` and serving the html in
Documentation/output. Since libbpf does not yet have comments in kernel
doc format, see kernel.org/doc/html/latest/doc-guide/kernel-doc.html for
an example so you can test this.

The advantage of this approach is to use the existing sphinx
infrastructure that the kernel has, and have libbpf docs in
the same place as everything else.

The current plan is to have the libbpf mirror sync the generated docs
and version them based on the libbpf releases which are cut on github.

This patch includes the addition of libbpf_api.rst which pulls comment
documentation from header files in libbpf under tools/lib/bpf/. The comment
docs would be of the standard kernel doc format.

Signed-off-by: Grant Seltzer <grantseltzer@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210618140459.9887-2-grantseltzer@gmail.com
2021-06-18 23:06:06 +02:00