Add selftest that combines two BPF programs within single BPF object
file such that one of the programs is using global variables, but can be
skipped at runtime on old kernels that don't support global data.
Another BPF program is written with the goal to be runnable on very old
kernels and only relies on explicitly accessed BPF maps.

Such test, run against old kernels (e.g., libbpf CI will run it against 4.9
kernel that doesn't support global data), allows to test the approach
and ensure that libbpf doesn't make unnecessary assumption about
necessary kernel features.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20211123200105.387855-2-andrii@kernel.org

Load global data maps lazily, if kernel is too old to support global
data. Make sure that programs are still correct by detecting if any of
the to-be-loaded programs have relocation against any of such maps.

This allows to solve the issue ([0]) with bpf_printk() and Clang
generating unnecessary and unreferenced .rodata.strX.Y sections, but it
also goes further along the CO-RE lines, allowing to have a BPF object
in which some code can work on very old kernels and relies only on BPF
maps explicitly, while other BPF programs might enjoy global variable
support. If such programs are correctly set to not load at runtime on
old kernels, bpf_object will load and function correctly now.

  [0] https://lore.kernel.org/bpf/CAK-59YFPU3qO+_pXWOH+c1LSA=8WA1yabJZfREjOEXNHAqgXNg@mail.gmail.com/

Fixes: aed65917 ("libbpf: Support multiple .rodata.* and .data.* BPF maps")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20211123200105.387855-1-andrii@kernel.org

Fix trivial typo in comment from 'oveflow' to 'overflow'.
Reported-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Drew Fustini <dfustini@baylibre.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211122070528.837806-1-dfustini@baylibre.com

bpf_program__set_extra_flags has just been introduced so we can still
change it without breaking users.

This new interface is a bit more flexible (for example if someone wants
to clear a flag).
Signed-off-by: Florent Revest <revest@chromium.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211119180035.1396139-1-revest@chromium.org

Add an artificial minimal example simulating compilers producing two
different types within a single CU that correspond to identical struct
definitions.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211117194114.347675-2-andrii@kernel.org

According to [0], compilers sometimes might produce duplicate DWARF
definitions for exactly the same struct/union within the same
compilation unit (CU). We've had similar issues with identical arrays
and handled them with a similar workaround in 6b6e6b1d ("libbpf:
Accomodate DWARF/compiler bug with duplicated identical arrays"). Do the
same for struct/union by ensuring that two structs/unions are exactly
the same, down to the integer values of field referenced type IDs.

Solving this more generically (allowing referenced types to be
equivalent, but using different type IDs, all within a single CU)
requires a huge complexity increase to handle many-to-many mappings
between canonidal and candidate type graphs. Before we invest in that,
let's see if this approach handles all the instances of this issue in
practice. Thankfully it's pretty rare, it seems.

  [0] https://lore.kernel.org/bpf/YXr2NFlJTAhHdZqq@krava/Reported-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211117194114.347675-1-andrii@kernel.org

Libbpf provided LIBBPF_MAJOR_VERSION and LIBBPF_MINOR_VERSION macros to
check libbpf version at compilation time. This doesn't cover all the
needs, though, because version of libbpf that application is compiled
against doesn't necessarily match the version of libbpf at runtime,
especially if libbpf is used as a shared library.

Add libbpf_major_version() and libbpf_minor_version() returning major
and minor versions, respectively, as integers. Also add a convenience
libbpf_version_string() for various tooling using libbpf to print out
libbpf version in a human-readable form. Currently it will return
"v0.6", but in the future it can contains some extra information, so the
format itself is not part of a stable API and shouldn't be relied upon.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20211118174054.2699477-1-andrii@kernel.org

[1] added s390 support to libbpf CI and added an ${ARCH} prefix to a
number of paths and identifiers in libbpf GitHub repo, which vmtest.sh
relies upon. Update these and make use of the new s390 support.

[1] https://github.com/libbpf/libbpf/pull/204Co-developed-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211118115225.1349726-1-iii@linux.ibm.com

xsk_configure_umem() needs hugepages to work in unaligned mode. So when
hugepages are not configured, 'unaligned' tests should be skipped which
is determined by the helper function hugepages_present(). This function
erroneously returns true with MAP_NORESERVE flag even when no hugepages
are configured. The removal of this flag fixes the issue.

The test TEST_TYPE_UNALIGNED_INV_DESC also needs to be skipped when
there are no hugepages. However, this was not skipped as there was no
check for presence of hugepages and hence was failing. The check to skip
the test has now been added.

Fixes: a4ba98dd (selftests: xsk: Add test for unaligned mode)
Signed-off-by: Tirthendu Sarkar <tirthendu.sarkar@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211117123613.22288-1-tirthendu.sarkar@intel.com

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

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

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

Fix warnings from checkstyle.pl
Signed-off-by: Yucong Sun <sunyucong@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211112192535.898352-4-fallentree@fb.com

Change log_fd to log_fp to reflect its type correctly.
Signed-off-by: Yucong Sun <sunyucong@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211112192535.898352-3-fallentree@fb.com

Makes it easier to find the summary line when there is a lot of logs to
scroll back.
Signed-off-by: Yucong Sun <sunyucong@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211112192535.898352-2-fallentree@fb.com

Add benchmark to measure overhead of uprobes and uretprobes. Also have
a baseline (no uprobe attached) benchmark.

On my dev machine, baseline benchmark can trigger 130M user_target()
invocations. When uprobe is attached, this falls to just 700K. With
uretprobe, we get down to 520K:

  $ sudo ./bench trig-uprobe-base -a
  Summary: hits  131.289 ± 2.872M/s

  # UPROBE
  $ sudo ./bench -a trig-uprobe-without-nop
  Summary: hits    0.729 ± 0.007M/s

  $ sudo ./bench -a trig-uprobe-with-nop
  Summary: hits    1.798 ± 0.017M/s

  # URETPROBE
  $ sudo ./bench -a trig-uretprobe-without-nop
  Summary: hits    0.508 ± 0.012M/s

  $ sudo ./bench -a trig-uretprobe-with-nop
  Summary: hits    0.883 ± 0.008M/s

So there is almost 2.5x performance difference between probing nop vs
non-nop instruction for entry uprobe. And 1.7x difference for uretprobe.

This means that non-nop uprobe overhead is around 1.4 microseconds for uprobe
and 2 microseconds for non-nop uretprobe.

For nop variants, uprobe and uretprobe overhead is down to 0.556 and
1.13 microseconds, respectively.

For comparison, just doing a very low-overhead syscall (with no BPF
programs attached anywhere) gives:

  $ sudo ./bench trig-base -a
  Summary: hits    4.830 ± 0.036M/s

So uprobes are about 2.67x slower than pure context switch.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211116013041.4072571-1-andrii@kernel.org

In the current code, the actual max tail call count is 33 which is greater
than MAX_TAIL_CALL_CNT (defined as 32). The actual limit is not consistent
with the meaning of MAX_TAIL_CALL_CNT and thus confusing at first glance.
We can see the historical evolution from commit 04fd61ab ("bpf: allow
bpf programs to tail-call other bpf programs") and commit f9dabe01
("bpf: Undo off-by-one in interpreter tail call count limit"). In order
to avoid changing existing behavior, the actual limit is 33 now, this is
reasonable.

After commit 874be05f ("bpf, tests: Add tail call test suite"), we can
see there exists failed testcase.

On all archs when CONFIG_BPF_JIT_ALWAYS_ON is not set:
 # echo 0 > /proc/sys/net/core/bpf_jit_enable
 # modprobe test_bpf
 # dmesg | grep -w FAIL
 Tail call error path, max count reached jited:0 ret 34 != 33 FAIL

On some archs:
 # echo 1 > /proc/sys/net/core/bpf_jit_enable
 # modprobe test_bpf
 # dmesg | grep -w FAIL
 Tail call error path, max count reached jited:1 ret 34 != 33 FAIL

Although the above failed testcase has been fixed in commit 18935a72
("bpf/tests: Fix error in tail call limit tests"), it would still be good
to change the value of MAX_TAIL_CALL_CNT from 32 to 33 to make the code
more readable.

The 32-bit x86 JIT was using a limit of 32, just fix the wrong comments and
limit to 33 tail calls as the constant MAX_TAIL_CALL_CNT updated. For the
mips64 JIT, use "ori" instead of "addiu" as suggested by Johan Almbladh.
For the riscv JIT, use RV_REG_TCC directly to save one register move as
suggested by Björn Töpel. For the other implementations, no function changes,
it does not change the current limit 33, the new value of MAX_TAIL_CALL_CNT
can reflect the actual max tail call count, the related tail call testcases
in test_bpf module and selftests can work well for the interpreter and the
JIT.

Here are the test results on x86_64:

 # uname -m
 x86_64
 # echo 0 > /proc/sys/net/core/bpf_jit_enable
 # modprobe test_bpf test_suite=test_tail_calls
 # dmesg | tail -1
 test_bpf: test_tail_calls: Summary: 8 PASSED, 0 FAILED, [0/8 JIT'ed]
 # rmmod test_bpf
 # echo 1 > /proc/sys/net/core/bpf_jit_enable
 # modprobe test_bpf test_suite=test_tail_calls
 # dmesg | tail -1
 test_bpf: test_tail_calls: Summary: 8 PASSED, 0 FAILED, [8/8 JIT'ed]
 # rmmod test_bpf
 # ./test_progs -t tailcalls
 #142 tailcalls:OK
 Summary: 1/11 PASSED, 0 SKIPPED, 0 FAILED
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Tested-by: Ilya Leoshkevich <iii@linux.ibm.com>
Acked-by: Björn Töpel <bjorn@kernel.org>
Acked-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/bpf/1636075800-3264-1-git-send-email-yangtiezhu@loongson.cn

Script test_bpftool_synctypes.py parses a number of files in the bpftool
directory (or even elsewhere in the repo) to make sure that the list of
types or options in those different files are consistent. Instead of
having fixed paths, let's make the directories configurable through
environment variable. This should make easier in the future to run the
script in a different setup, for example on an out-of-tree bpftool
mirror with a different layout.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211115225844.33943-4-quentin@isovalent.com

test_bpftool_synctypes.py helps detecting inconsistencies in bpftool
between the different list of types and options scattered in the
sources, the documentation, and the bash completion. For options that
apply to all bpftool commands, the script had a hardcoded list of
values, and would use them to check whether the man pages are
up-to-date. When writing the script, it felt acceptable to have this
list in order to avoid to open and parse bpftool's main.h every time,
and because the list of global options in bpftool doesn't change so
often.

However, this is prone to omissions, and we recently added a new
-l|--legacy option which was described in common_options.rst, but not
listed in the options summary of each manual page. The script did not
complain, because it keeps comparing the hardcoded list to the (now)
outdated list in the header file.

To address the issue, this commit brings the following changes:

- Options that are common to all bpftool commands (--json, --pretty, and
  --debug) are moved to a dedicated file, and used in the definition of
  a RST substitution. This substitution is used in the sources of all
  the man pages.

- This list of common options is updated, with the addition of the new
  -l|--legacy option.

- The script test_bpftool_synctypes.py is updated to compare:
    - Options specific to a command, found in C files, for the
      interactive help messages, with the same specific options from the
      relevant man page for that command.
    - Common options, checked just once: the list in main.h is
      compared with the new list in substitutions.rst.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211115225844.33943-3-quentin@isovalent.com

Most files in the kernel repository have a SPDX tags. The files that
don't have such a tag (or another license boilerplate) tend to fall
under the GPL-2.0 license. In the past, bpftool's Makefile (for example)
has been marked as GPL-2.0 for that reason, when in fact all bpftool is
dual-licensed.

To prevent a similar confusion from happening with the RST documentation
files for bpftool, let's explicitly mark all files as dual-licensed.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211115225844.33943-2-quentin@isovalent.com

Without previous libbpf patch, the following error will occur:

  $ ./test_progs -t btf
  ...
  do_test_dedup:FAIL:check btf_dedup failed errno:-22#13/205 btf/dedup: btf_type_tag #5, struct:FAIL

And the previous libbpf patch fixed the issue.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211115163943.3922547-1-yhs@fb.com

Commit 2dc1e488 ("libbpf: Support BTF_KIND_TYPE_TAG") added the
BTF_KIND_TYPE_TAG support. But to test vmlinux build with ...

  #define __user __attribute__((btf_type_tag("user")))

... I needed to sync libbpf repo and manually copy libbpf sources to
pahole. To simplify process, I used BTF_KIND_RESTRICT to simulate the
BTF_KIND_TYPE_TAG with vmlinux build as "restrict" modifier is barely
used in kernel.

But this approach missed one case in dedup with structures where
BTF_KIND_RESTRICT is handled and BTF_KIND_TYPE_TAG is not handled in
btf_dedup_is_equiv(), and this will result in a pahole dedup failure.
This patch fixed this issue and a selftest is added in the subsequent
patch to test this scenario.

The other missed handling is in btf__resolve_size(). Currently the compiler
always emit like PTR->TYPE_TAG->... so in practice we don't hit the missing
BTF_KIND_TYPE_TAG handling issue with compiler generated code. But lets
add case BTF_KIND_TYPE_TAG in the switch statement to be future proof.

Fixes: 2dc1e488 ("libbpf: Support BTF_KIND_TYPE_TAG")
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211115163937.3922235-1-yhs@fb.com

+ bpftool --legacy --version
bpftool v5.15.0
features: libbfd, skeletons
+ bpftool --version
bpftool v5.15.0
features: libbfd, libbpf_strict, skeletons

+ bpftool --legacy --help
Usage: bpftool [OPTIONS] OBJECT { COMMAND | help }
       bpftool batch file FILE
       bpftool version

       OBJECT := { prog | map | link | cgroup | perf | net | feature | btf | gen | struct_ops | iter }
       OPTIONS := { {-j|--json} [{-p|--pretty}] | {-d|--debug} | {-l|--legacy} |
                    {-V|--version} }
+ bpftool --help
Usage: bpftool [OPTIONS] OBJECT { COMMAND | help }
       bpftool batch file FILE
       bpftool version

       OBJECT := { prog | map | link | cgroup | perf | net | feature | btf | gen | struct_ops | iter }
       OPTIONS := { {-j|--json} [{-p|--pretty}] | {-d|--debug} | {-l|--legacy} |
                    {-V|--version} }

+ bpftool --legacy
Usage: bpftool [OPTIONS] OBJECT { COMMAND | help }
       bpftool batch file FILE
       bpftool version

       OBJECT := { prog | map | link | cgroup | perf | net | feature | btf | gen | struct_ops | iter }
       OPTIONS := { {-j|--json} [{-p|--pretty}] | {-d|--debug} | {-l|--legacy} |
                    {-V|--version} }
+ bpftool
Usage: bpftool [OPTIONS] OBJECT { COMMAND | help }
       bpftool batch file FILE
       bpftool version

       OBJECT := { prog | map | link | cgroup | perf | net | feature | btf | gen | struct_ops | iter }
       OPTIONS := { {-j|--json} [{-p|--pretty}] | {-d|--debug} | {-l|--legacy} |
                    {-V|--version} }

+ bpftool --legacy version
bpftool v5.15.0
features: libbfd, skeletons
+ bpftool version
bpftool v5.15.0
features: libbfd, libbpf_strict, skeletons

+ bpftool --json --legacy version
{"version":"5.15.0","features":{"libbfd":true,"libbpf_strict":false,"skeletons":true}}
+ bpftool --json version
{"version":"5.15.0","features":{"libbfd":true,"libbpf_strict":true,"skeletons":true}}
Suggested-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20211116000448.2918854-1-sdf@google.com

Daniel Borkmann says:

====================
pull-request: bpf-next 2021-11-15

We've added 72 non-merge commits during the last 13 day(s) which contain
a total of 171 files changed, 2728 insertions(+), 1143 deletions(-).

The main changes are:

1) Add btf_type_tag attributes to bring kernel annotations like __user/__rcu to
   BTF such that BPF verifier will be able to detect misuse, from Yonghong Song.

2) Big batch of libbpf improvements including various fixes, future proofing APIs,
   and adding a unified, OPTS-based bpf_prog_load() low-level API, from Andrii Nakryiko.

3) Add ingress_ifindex to BPF_SK_LOOKUP program type for selectively applying the
   programmable socket lookup logic to packets from a given netdev, from Mark Pashmfouroush.

4) Remove the 128M upper JIT limit for BPF programs on arm64 and add selftest to
   ensure exception handling still works, from Russell King and Alan Maguire.

5) Add a new bpf_find_vma() helper for tracing to map an address to the backing
   file such as shared library, from Song Liu.

6) Batch of various misc fixes to bpftool, fixing a memory leak in BPF program dump,
   updating documentation and bash-completion among others, from Quentin Monnet.

7) Deprecate libbpf bpf_program__get_prog_info_linear() API and migrate its users as
   the API is heavily tailored around perf and is non-generic, from Dave Marchevsky.

8) Enable libbpf's strict mode by default in bpftool and add a --legacy option as an
   opt-out for more relaxed BPF program requirements, from Stanislav Fomichev.

9) Fix bpftool to use libbpf_get_error() to check for errors, from Hengqi Chen.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (72 commits)
  bpftool: Use libbpf_get_error() to check error
  bpftool: Fix mixed indentation in documentation
  bpftool: Update the lists of names for maps and prog-attach types
  bpftool: Fix indent in option lists in the documentation
  bpftool: Remove inclusion of utilities.mak from Makefiles
  bpftool: Fix memory leak in prog_dump()
  selftests/bpf: Fix a tautological-constant-out-of-range-compare compiler warning
  selftests/bpf: Fix an unused-but-set-variable compiler warning
  bpf: Introduce btf_tracing_ids
  bpf: Extend BTF_ID_LIST_GLOBAL with parameter for number of IDs
  bpftool: Enable libbpf's strict mode by default
  docs/bpf: Update documentation for BTF_KIND_TYPE_TAG support
  selftests/bpf: Clarify llvm dependency with btf_tag selftest
  selftests/bpf: Add a C test for btf_type_tag
  selftests/bpf: Rename progs/tag.c to progs/btf_decl_tag.c
  selftests/bpf: Test BTF_KIND_DECL_TAG for deduplication
  selftests/bpf: Add BTF_KIND_TYPE_TAG unit tests
  selftests/bpf: Test libbpf API function btf__add_type_tag()
  bpftool: Support BTF_KIND_TYPE_TAG
  libbpf: Support BTF_KIND_TYPE_TAG
  ...
====================

Link: https://lore.kernel.org/r/20211115162008.25916-1-daniel@iogearbox.netSigned-off-by: Jakub Kicinski <kuba@kernel.org>

This reverts commit 71812af7, reversing
changes made to cc0be1ad.

Wolfram Sang says:

Please revert. Besides the driver in net, it modifies the I2C core
code. This has not been acked by the I2C maintainer (in this case me).
So, please don't pull this in via the net tree. The question raised here
(extending SMBus calls to 255 byte) is complicated because we need ABI
backwards compatibility.

Link: https://lore.kernel.org/all/YZJ9H4eM%2FM7OXVN0@shikoro/Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Russell King says:

====================
introduce generic phylink validation

The various validate method implementations we have in phylink users
have been quite repetitive but also prone to bugs. These patches
introduce a generic implementation which relies solely on the
supported_interfaces bitmap introduced during last cycle, and in the
first patch, a bit array of MAC capabilities.

MAC drivers are free to continue to do their own thing if they have
special requirements - such as mvneta and mvpp2 which do not support
1000base-X without AN enabled. Most implementations currently in the
kernel can be converted to call phylink_generic_validate() directly
from the phylink MAC operations structure once they fill in the
supported_interfaces and mac_capabilities members of phylink_config.

This series introduces the generic implementation, and converts mvneta
and mvpp2 to use it.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Convert mvpp2 to use phylink_generic_validate() for the bulk of its
validate() implementation. This network adapter has a restriction
that for 802.3z links, autonegotiation must be enabled.
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

Convert mvneta to use phylink_generic_validate() for the bulk of its
validate() implementation. This network adapter has a restriction
that for 802.3z links, autonegotiation must be enabled.
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add a generic validate() implementation using the supported_interfaces
and a bitmask of MAC pause/speed/duplex capabilities. This allows us
to entirely eliminate many driver private validate() implementations.

We expose the underlying phylink_get_linkmodes() function so that
drivers which have special needs can still benefit from conversion.
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

CHECK   drivers/net/wan/fsl_ucc_hdlc.c
drivers/net/wan/fsl_ucc_hdlc.c:309:57: warning: incorrect type in argument 2 (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:309:57:    expected void [noderef] __iomem *
drivers/net/wan/fsl_ucc_hdlc.c:309:57:    got restricted __be16 *
drivers/net/wan/fsl_ucc_hdlc.c:311:46: warning: incorrect type in argument 2 (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:311:46:    expected void [noderef] __iomem *
drivers/net/wan/fsl_ucc_hdlc.c:311:46:    got restricted __be32 *
drivers/net/wan/fsl_ucc_hdlc.c:320:57: warning: incorrect type in argument 2 (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:320:57:    expected void [noderef] __iomem *
drivers/net/wan/fsl_ucc_hdlc.c:320:57:    got restricted __be16 *
drivers/net/wan/fsl_ucc_hdlc.c:322:46: warning: incorrect type in argument 2 (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:322:46:    expected void [noderef] __iomem *
drivers/net/wan/fsl_ucc_hdlc.c:322:46:    got restricted __be32 *
drivers/net/wan/fsl_ucc_hdlc.c:372:29: warning: incorrect type in assignment (different base types)
drivers/net/wan/fsl_ucc_hdlc.c:372:29:    expected unsigned short [usertype]
drivers/net/wan/fsl_ucc_hdlc.c:372:29:    got restricted __be16 [usertype]
drivers/net/wan/fsl_ucc_hdlc.c:379:36: warning: restricted __be16 degrades to integer
drivers/net/wan/fsl_ucc_hdlc.c:402:12: warning: incorrect type in assignment (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:402:12:    expected struct qe_bd [noderef] __iomem *bd
drivers/net/wan/fsl_ucc_hdlc.c:402:12:    got struct qe_bd *curtx_bd
drivers/net/wan/fsl_ucc_hdlc.c:425:20: warning: incorrect type in assignment (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:425:20:    expected struct qe_bd [noderef] __iomem *[assigned] bd
drivers/net/wan/fsl_ucc_hdlc.c:425:20:    got struct qe_bd *tx_bd_base
drivers/net/wan/fsl_ucc_hdlc.c:427:16: error: incompatible types in comparison expression (different address spaces):
drivers/net/wan/fsl_ucc_hdlc.c:427:16:    struct qe_bd [noderef] __iomem *
drivers/net/wan/fsl_ucc_hdlc.c:427:16:    struct qe_bd *
drivers/net/wan/fsl_ucc_hdlc.c:462:33: warning: incorrect type in argument 1 (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:506:41: warning: incorrect type in argument 1 (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:528:33: warning: incorrect type in argument 1 (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:552:38: warning: incorrect type in argument 1 (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:596:67: warning: incorrect type in argument 2 (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:611:41: warning: incorrect type in argument 1 (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:851:38: warning: incorrect type in initializer (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:854:40: warning: incorrect type in argument 1 (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:855:40: warning: incorrect type in argument 1 (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:858:39: warning: incorrect type in argument 1 (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:861:37: warning: incorrect type in argument 2 (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:866:38: warning: incorrect type in initializer (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:868:21: warning: incorrect type in argument 1 (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:870:40: warning: incorrect type in argument 2 (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:871:40: warning: incorrect type in argument 2 (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:873:39: warning: incorrect type in argument 2 (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:993:57: warning: incorrect type in argument 2 (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:995:46: warning: incorrect type in argument 2 (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:1004:57: warning: incorrect type in argument 2 (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:1006:46: warning: incorrect type in argument 2 (different address spaces)
drivers/net/wan/fsl_ucc_hdlc.c:412:35: warning: dereference of noderef expression
drivers/net/wan/fsl_ucc_hdlc.c:412:35: warning: dereference of noderef expression
drivers/net/wan/fsl_ucc_hdlc.c:724:29: warning: dereference of noderef expression
drivers/net/wan/fsl_ucc_hdlc.c:815:21: warning: dereference of noderef expression
drivers/net/wan/fsl_ucc_hdlc.c:1021:29: warning: dereference of noderef expression

Most of the warnings are due to DMA memory being incorrectly handled as IO memory.
Fix it by doing direct read/write and doing proper dma_rmb() / dma_wmb().

Other problems are type mismatches or lack of use of IO accessors.

Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lkml.org/lkml/2021/11/12/647Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>

Use the macro 'swap()' defined in 'include/linux/minmax.h' to avoid
opencoding it.
Signed-off-by: Yihao Han <hanyihao@vivo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ARRAY_SIZE defined in <linux/kernel.h> is safer than self-defined
macros to get size of an array such as ARRAY_LEN used here. Because
ARRAY_SIZE uses __must_be_array(arr) to ensure arr is really an array.
Reported-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
Signed-off-by: Guo Zhengkui <guozhengkui@vivo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

On low-effciency embedded platforms, transmission performance is poor
due to on Bulk-out with single packet.
Adding TSO feature improves the transmission performance and reduces
the number of interrupt caused by Bulk-out complete.

Reference to module, net: usb: aqc111.
Signed-off-by: Jacky Chou <jackychou@asix.com.tw>
Signed-off-by: David S. Miller <davem@davemloft.net>

Matt Johnston says:

====================
MCTP I2C driver

This patch series adds a netdev driver providing MCTP transport over
I2C.

It applies against net-next using recent MCTP changes there, though also
has I2C core changes for review. I'll leave it to maintainers where it
should be applied - please let me know if it needs to be submitted
differently.

The I2C patches were previously sent as RFC though the only feedback
there was an ack to 255 bytes for aspeed.

The dt-bindings patch went through review on the list.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Provides MCTP network transport over an I2C bus, as specified in
DMTF DSP0237. All messages between nodes are sent as SMBus Block Writes.

Each I2C bus to be used for MCTP is flagged in devicetree by a
'mctp-controller' property on the bus node. Each flagged bus gets a
mctpi2cX net device created based on the bus number. A
'mctp-i2c-controller' I2C client needs to be added under the adapter. In
an I2C mux situation the mctp-i2c-controller node must be attached only
to the root I2C bus. The I2C client will handle incoming I2C slave block
write data for subordinate busses as well as its own bus.

In configurations without devicetree a driver instance can be attached
to a bus using the I2C slave new_device mechanism.

The MCTP core will hold/release the MCTP I2C device while responses
are pending (a 6 second timeout or once a socket is closed, response
received etc). While held the MCTP I2C driver will lock the I2C bus so
that the correct I2C mux remains selected while responses are received.

(Ideally we would just lock the mux to keep the current bus selected for
the response rather than a full I2C bus lock, but that isn't exposed in
the I2C mux API)

This driver requires I2C adapters that allow 255 byte transfers
(SMBus 3.0) as the specification requires a minimum MTU of 68 bytes.
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

Used to define a local endpoint to communicate with MCTP peripherals
attached to an I2C bus. This I2C endpoint can communicate with remote
MCTP devices on the I2C bus.

In the example I2C topology below (matching the second yaml example) we
have MCTP devices on busses i2c1 and i2c6. MCTP-supporting busses are
indicated by the 'mctp-controller' DT property on an I2C bus node.

A mctp-i2c-controller I2C client DT node is placed at the top of the
mux topology, since only the root I2C adapter will support I2C slave
functionality.
                                               .-------.
                                               |eeprom |
    .------------.     .------.               /'-------'
    | adapter    |     | mux  --@0,i2c5------'
    | i2c1       ----.*|      --@1,i2c6--.--.
    |............|    \'------'           \  \  .........
    | mctp-i2c-  |     \                   \  \ .mctpB  .
    | controller |      \                   \  '.0x30   .
    |            |       \  .........        \  '.......'
    | 0x50       |        \ .mctpA  .         \ .........
    '------------'         '.0x1d   .          '.mctpC  .
                            '.......'          '.0x31   .
                                                '.......'
(mctpX boxes above are remote MCTP devices not included in the DT at
present, they can be hotplugged/probed at runtime. A DT binding for
specific fixed MCTP devices could be added later if required)
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

255 byte support has been tested on a npcm750 board
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Reviewed-by: Tali Perry <tali.perry1@gmail.com>
Reviewed-by: Patrick Venture <venture@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

255 byte transfers have been tested on an AST2500 board
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

I2C_SMBUS is limited to 32 bytes due to compatibility with the
32 byte i2c_smbus_data.block

I2C_RDWR allows larger transfers if sufficient sized buffers are passed.
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

SMBus 3.0 increased the maximum block transfer size from 32 bytes to
255 bytes. We increase the size of struct i2c_smbus_data's block[]
member.

i2c_smbus_xfer() and i2c_smbus_xfer_emulated() now support 255 byte
block operations, other block functions remain limited to 32 bytes for
compatibility with existing callers.

We allow adapters to indicate support for the larger size with
I2C_FUNC_SMBUS_V3_BLOCK. Most emulated drivers should be able to use 255
byte blocks by replacing I2C_SMBUS_BLOCK_MAX with I2C_SMBUS_V3_BLOCK_MAX
though some will have hardware limitations that need testing.
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>