Currently, btf only supports upto 32bit enum value with BTF_KIND_ENUM.
But in kernel, some enum has 64bit values, e.g., in uapi bpf.h, we have
enum {
BPF_F_INDEX_MASK = 0xffffffffULL,
BPF_F_CURRENT_CPU = BPF_F_INDEX_MASK,
BPF_F_CTXLEN_MASK = (0xfffffULL << 32),
};
With BTF_KIND_ENUM, the value for BPF_F_CTXLEN_MASK will be encoded
as 0 which is incorrect.
To solve this problem, BTF_KIND_ENUM64 is proposed in this patch set
to support enum 64bit values. Also, since sometimes there is a need
to generate C code from btf, e.g., vmlinux.h, btf kflag support
is also added for BTF_KIND_ENUM and BTF_KIND_ENUM64, which will
permit proper value printout, signed or unsigned.
In the rest of this patch set, Patch #1 added kernel support,
Patches #2 - #4 for libbpf, Patch #5 for bpftool. Patches #6 - #11
are for various selftests, and Patch #12 added BTF_KIND_ENUM64
in btf documentation.
Yonghong Song (12):
bpf: Add btf enum64 support
libbpf: Permit 64bit relocation value
libbpf: Fix an error in 64bit relocation value computation
libbpf: Add btf enum64 support
bpftool: Add btf enum64 support
selftests/bpf: Fix selftests failure
selftests/bpf: Test new libbpf enum32/enum64 API functions
selftests/bpf: Add BTF_KIND_ENUM64 unit tests
selftests/bpf: Test BTF_KIND_ENUM64 for deduplication
selftests/bpf: add a test for enum64 value relocation
selftests/bpf: Clarify llvm dependency with possible selftest failures
docs/bpf: Update documentation for BTF_KIND_ENUM64 support
Documentation/bpf/btf.rst | 34 ++-
include/linux/btf.h | 18 +-
include/uapi/linux/btf.h | 17 +-
kernel/bpf/btf.c | 132 +++++++++-
tools/bpf/bpftool/btf.c | 47 +++-
tools/bpf/bpftool/btf_dumper.c | 32 +++
tools/bpf/bpftool/gen.c | 1 +
tools/include/uapi/linux/btf.h | 17 +-
tools/lib/bpf/btf.c | 226 +++++++++++++++++-
tools/lib/bpf/btf.h | 21 ++
tools/lib/bpf/btf_dump.c | 94 ++++++--
tools/lib/bpf/libbpf.c | 64 ++++-
tools/lib/bpf/libbpf.map | 4 +
tools/lib/bpf/libbpf_internal.h | 2 +
tools/lib/bpf/linker.c | 2 +
tools/lib/bpf/relo_core.c | 119 +++++----
tools/lib/bpf/relo_core.h | 4 +-
tools/testing/selftests/bpf/README.rst | 18 ++
tools/testing/selftests/bpf/btf_helpers.c | 21 +-
tools/testing/selftests/bpf/prog_tests/btf.c | 128 ++++++++--
.../selftests/bpf/prog_tests/btf_dump.c | 10 +-
.../selftests/bpf/prog_tests/btf_write.c | 120 +++++++---
.../selftests/bpf/prog_tests/core_reloc.c | 43 ++++
.../bpf/progs/btf__core_reloc_enum64val.c | 3 +
.../progs/btf__core_reloc_enum64val___diff.c | 3 +
.../btf__core_reloc_enum64val___err_missing.c | 3 +
...btf__core_reloc_enum64val___val3_missing.c | 3 +
.../bpf/progs/btf_dump_test_case_syntax.c | 2 +-
.../selftests/bpf/progs/core_reloc_types.h | 47 ++++
.../bpf/progs/test_core_reloc_enum64val.c | 53 ++++
tools/testing/selftests/bpf/test_btf.h | 1 +
31 files changed, 1126 insertions(+), 163 deletions(-)
create mode 100644 tools/testing/selftests/bpf/progs/btf__core_reloc_enum64val.c
create mode 100644 tools/testing/selftests/bpf/progs/btf__core_reloc_enum64val___diff.c
create mode 100644 tools/testing/selftests/bpf/progs/btf__core_reloc_enum64val___err_missing.c
create mode 100644 tools/testing/selftests/bpf/progs/btf__core_reloc_enum64val___val3_missing.c
create mode 100644 tools/testing/selftests/bpf/progs/test_core_reloc_enum64val.c
--
2.30.2
