From: Andrii Nakryiko andrii@kernel.org
mainline inclusion from mainline-5.14-rc1 commit fdbf5ddeb855a80831af2e5bb9db9218926e6789 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I5EUVD CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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For better future extensibility add per-file linker options. Currently the set of available options is empty. This changes bpf_linker__add_file() API, but it's not a breaking change as bpf_linker APIs hasn't been released yet.
Signed-off-by: Andrii Nakryiko andrii@kernel.org Signed-off-by: Alexei Starovoitov ast@kernel.org Link: https://lore.kernel.org/bpf/20210507054119.270888-3-andrii@kernel.org (cherry picked from commit fdbf5ddeb855a80831af2e5bb9db9218926e6789) Signed-off-by: Wang Yufen wangyufen@huawei.com --- tools/bpf/bpftool/gen.c | 2 +- tools/lib/bpf/libbpf.h | 10 +++++++++- tools/lib/bpf/linker.c | 16 ++++++++++++---- 3 files changed, 22 insertions(+), 6 deletions(-)
diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index 440a2fcb6441..06fee4a2910a 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -638,7 +638,7 @@ static int do_object(int argc, char **argv) while (argc) { file = GET_ARG();
- err = bpf_linker__add_file(linker, file); + err = bpf_linker__add_file(linker, file, NULL); if (err) { p_err("failed to link '%s': %s (%d)", file, strerror(err), err); goto out; diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index b92012b4a2f7..9f2c588faf3d 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -771,10 +771,18 @@ struct bpf_linker_opts { }; #define bpf_linker_opts__last_field sz
+struct bpf_linker_file_opts { + /* size of this struct, for forward/backward compatiblity */ + size_t sz; +}; +#define bpf_linker_file_opts__last_field sz + struct bpf_linker;
LIBBPF_API struct bpf_linker *bpf_linker__new(const char *filename, struct bpf_linker_opts *opts); -LIBBPF_API int bpf_linker__add_file(struct bpf_linker *linker, const char *filename); +LIBBPF_API int bpf_linker__add_file(struct bpf_linker *linker, + const char *filename, + const struct bpf_linker_file_opts *opts); LIBBPF_API int bpf_linker__finalize(struct bpf_linker *linker); LIBBPF_API void bpf_linker__free(struct bpf_linker *linker);
diff --git a/tools/lib/bpf/linker.c b/tools/lib/bpf/linker.c index f40fa50e9a89..b82a78d6d957 100644 --- a/tools/lib/bpf/linker.c +++ b/tools/lib/bpf/linker.c @@ -158,7 +158,9 @@ struct bpf_linker {
static int init_output_elf(struct bpf_linker *linker, const char *file);
-static int linker_load_obj_file(struct bpf_linker *linker, const char *filename, struct src_obj *obj); +static int linker_load_obj_file(struct bpf_linker *linker, const char *filename, + const struct bpf_linker_file_opts *opts, + struct src_obj *obj); static int linker_sanity_check_elf(struct src_obj *obj); static int linker_sanity_check_elf_symtab(struct src_obj *obj, struct src_sec *sec); static int linker_sanity_check_elf_relos(struct src_obj *obj, struct src_sec *sec); @@ -435,15 +437,19 @@ static int init_output_elf(struct bpf_linker *linker, const char *file) return 0; }
-int bpf_linker__add_file(struct bpf_linker *linker, const char *filename) +int bpf_linker__add_file(struct bpf_linker *linker, const char *filename, + const struct bpf_linker_file_opts *opts) { struct src_obj obj = {}; int err = 0;
+ if (!OPTS_VALID(opts, bpf_linker_file_opts)) + return -EINVAL; + if (!linker->elf) return -EINVAL;
- err = err ?: linker_load_obj_file(linker, filename, &obj); + err = err ?: linker_load_obj_file(linker, filename, opts, &obj); err = err ?: linker_append_sec_data(linker, &obj); err = err ?: linker_append_elf_syms(linker, &obj); err = err ?: linker_append_elf_relos(linker, &obj); @@ -529,7 +535,9 @@ static struct src_sec *add_src_sec(struct src_obj *obj, const char *sec_name) return sec; }
-static int linker_load_obj_file(struct bpf_linker *linker, const char *filename, struct src_obj *obj) +static int linker_load_obj_file(struct bpf_linker *linker, const char *filename, + const struct bpf_linker_file_opts *opts, + struct src_obj *obj) { #if __BYTE_ORDER == __LITTLE_ENDIAN const int host_endianness = ELFDATA2LSB;