diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h
index 91f0ad0e0325e4692840bab4826ff0203c969bee..2a55320d87d0d3c15bcb1c78df76a5ea5c60cc88 100644
--- a/tools/lib/bpf/btf.h
+++ b/tools/lib/bpf/btf.h
@@ -57,14 +57,16 @@ LIBBPF_API struct btf_ext *btf_ext__new(__u8 *data, __u32 size);
LIBBPF_API void btf_ext__free(struct btf_ext *btf_ext);
LIBBPF_API const void *btf_ext__get_raw_data(const struct btf_ext *btf_ext,
__u32 *size);
-LIBBPF_API int btf_ext__reloc_func_info(const struct btf *btf,
- const struct btf_ext *btf_ext,
- const char *sec_name, __u32 insns_cnt,
- void **func_info, __u32 *cnt);
-LIBBPF_API int btf_ext__reloc_line_info(const struct btf *btf,
- const struct btf_ext *btf_ext,
- const char *sec_name, __u32 insns_cnt,
- void **line_info, __u32 *cnt);
+LIBBPF_API LIBBPF_DEPRECATED("btf_ext__reloc_func_info was never meant as a public API and has wrong assumptions embedded in it; it will be removed in the future libbpf versions")
+int btf_ext__reloc_func_info(const struct btf *btf,
+ const struct btf_ext *btf_ext,
+ const char *sec_name, __u32 insns_cnt,
+ void **func_info, __u32 *cnt);
+LIBBPF_API LIBBPF_DEPRECATED("btf_ext__reloc_line_info was never meant as a public API and has wrong assumptions embedded in it; it will be removed in the future libbpf versions")
+int btf_ext__reloc_line_info(const struct btf *btf,
+ const struct btf_ext *btf_ext,
+ const char *sec_name, __u32 insns_cnt,
+ void **line_info, __u32 *cnt);
LIBBPF_API __u32 btf_ext__func_info_rec_size(const struct btf_ext *btf_ext);
LIBBPF_API __u32 btf_ext__line_info_rec_size(const struct btf_ext *btf_ext);
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 4e32a1028379ebbcffc96969fe91c98403dea321..ca2b5c9145da646dbd87c360e22a14599cd4c732 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -4241,75 +4241,6 @@ bpf_object__create_maps(struct bpf_object *obj)
return err;
}
-static int
-check_btf_ext_reloc_err(struct bpf_program *prog, int err,
- void *btf_prog_info, const char *info_name)
-{
- if (err != -ENOENT) {
- pr_warn("Error in loading %s for sec %s.\n",
- info_name, prog->section_name);
- return err;
- }
-
- /* err == -ENOENT (i.e. prog->section_name not found in btf_ext) */
-
- if (btf_prog_info) {
- /*
- * Some info has already been found but has problem
- * in the last btf_ext reloc. Must have to error out.
- */
- pr_warn("Error in relocating %s for sec %s.\n",
- info_name, prog->section_name);
- return err;
- }
-
- /* Have problem loading the very first info. Ignore the rest. */
- pr_warn("Cannot find %s for main program sec %s. Ignore all %s.\n",
- info_name, prog->section_name, info_name);
- return 0;
-}
-
-static int
-bpf_program_reloc_btf_ext(struct bpf_program *prog, struct bpf_object *obj,
- const char *section_name, __u32 insn_offset)
-{
- int err;
-
- if (!insn_offset || prog->func_info) {
- /*
- * !insn_offset => main program
- *
- * For sub prog, the main program's func_info has to
- * be loaded first (i.e. prog->func_info != NULL)
- */
- err = btf_ext__reloc_func_info(obj->btf, obj->btf_ext,
- section_name, insn_offset,
- &prog->func_info,
- &prog->func_info_cnt);
- if (err)
- return check_btf_ext_reloc_err(prog, err,
- prog->func_info,
- "bpf_func_info");
-
- prog->func_info_rec_size = btf_ext__func_info_rec_size(obj->btf_ext);
- }
-
- if (!insn_offset || prog->line_info) {
- err = btf_ext__reloc_line_info(obj->btf, obj->btf_ext,
- section_name, insn_offset,
- &prog->line_info,
- &prog->line_info_cnt);
- if (err)
- return check_btf_ext_reloc_err(prog, err,
- prog->line_info,
- "bpf_line_info");
-
- prog->line_info_rec_size = btf_ext__line_info_rec_size(obj->btf_ext);
- }
-
- return 0;
-}
-
#define BPF_CORE_SPEC_MAX_LEN 64
/* represents BPF CO-RE field or array element accessor */
@@ -5855,6 +5786,147 @@ bpf_object__relocate_data(struct bpf_object *obj, struct bpf_program *prog)
return 0;
}
+static int adjust_prog_btf_ext_info(const struct bpf_object *obj,
+ const struct bpf_program *prog,
+ const struct btf_ext_info *ext_info,
+ void **prog_info, __u32 *prog_rec_cnt,
+ __u32 *prog_rec_sz)
+{
+ void *copy_start = NULL, *copy_end = NULL;
+ void *rec, *rec_end, *new_prog_info;
+ const struct btf_ext_info_sec *sec;
+ size_t old_sz, new_sz;
+ const char *sec_name;
+ int i, off_adj;
+
+ for_each_btf_ext_sec(ext_info, sec) {
+ sec_name = btf__name_by_offset(obj->btf, sec->sec_name_off);
+ if (!sec_name)
+ return -EINVAL;
+ if (strcmp(sec_name, prog->section_name) != 0)
+ continue;
+
+ for_each_btf_ext_rec(ext_info, sec, i, rec) {
+ __u32 insn_off = *(__u32 *)rec / BPF_INSN_SZ;
+
+ if (insn_off < prog->sec_insn_off)
+ continue;
+ if (insn_off >= prog->sec_insn_off + prog->sec_insn_cnt)
+ break;
+
+ if (!copy_start)
+ copy_start = rec;
+ copy_end = rec + ext_info->rec_size;
+ }
+
+ if (!copy_start)
+ return -ENOENT;
+
+ /* append func/line info of a given (sub-)program to the main
+ * program func/line info
+ */
+ old_sz = (*prog_rec_cnt) * ext_info->rec_size;
+ new_sz = old_sz + (copy_end - copy_start);
+ new_prog_info = realloc(*prog_info, new_sz);
+ if (!new_prog_info)
+ return -ENOMEM;
+ *prog_info = new_prog_info;
+ *prog_rec_cnt = new_sz / ext_info->rec_size;
+ memcpy(new_prog_info + old_sz, copy_start, copy_end - copy_start);
+
+ /* Kernel instruction offsets are in units of 8-byte
+ * instructions, while .BTF.ext instruction offsets generated
+ * by Clang are in units of bytes. So convert Clang offsets
+ * into kernel offsets and adjust offset according to program
+ * relocated position.
+ */
+ off_adj = prog->sub_insn_off - prog->sec_insn_off;
+ rec = new_prog_info + old_sz;
+ rec_end = new_prog_info + new_sz;
+ for (; rec < rec_end; rec += ext_info->rec_size) {
+ __u32 *insn_off = rec;
+
+ *insn_off = *insn_off / BPF_INSN_SZ + off_adj;
+ }
+ *prog_rec_sz = ext_info->rec_size;
+ return 0;
+ }
+
+ return -ENOENT;
+}
+
+static int
+reloc_prog_func_and_line_info(const struct bpf_object *obj,
+ struct bpf_program *main_prog,
+ const struct bpf_program *prog)
+{
+ int err;
+
+ /* no .BTF.ext relocation if .BTF.ext is missing or kernel doesn't
+ * supprot func/line info
+ */
+ if (!obj->btf_ext || !kernel_supports(FEAT_BTF_FUNC))
+ return 0;
+
+ /* only attempt func info relocation if main program's func_info
+ * relocation was successful
+ */
+ if (main_prog != prog && !main_prog->func_info)
+ goto line_info;
+
+ err = adjust_prog_btf_ext_info(obj, prog, &obj->btf_ext->func_info,
+ &main_prog->func_info,
+ &main_prog->func_info_cnt,
+ &main_prog->func_info_rec_size);
+ if (err) {
+ if (err != -ENOENT) {
+ pr_warn("prog '%s': error relocating .BTF.ext function info: %d\n",
+ prog->name, err);
+ return err;
+ }
+ if (main_prog->func_info) {
+ /*
+ * Some info has already been found but has problem
+ * in the last btf_ext reloc. Must have to error out.
+ */
+ pr_warn("prog '%s': missing .BTF.ext function info.\n", prog->name);
+ return err;
+ }
+ /* Have problem loading the very first info. Ignore the rest. */
+ pr_warn("prog '%s': missing .BTF.ext function info for the main program, skipping all of .BTF.ext func info.\n",
+ prog->name);
+ }
+
+line_info:
+ /* don't relocate line info if main program's relocation failed */
+ if (main_prog != prog && !main_prog->line_info)
+ return 0;
+
+ err = adjust_prog_btf_ext_info(obj, prog, &obj->btf_ext->line_info,
+ &main_prog->line_info,
+ &main_prog->line_info_cnt,
+ &main_prog->line_info_rec_size);
+ if (err) {
+ if (err != -ENOENT) {
+ pr_warn("prog '%s': error relocating .BTF.ext line info: %d\n",
+ prog->name, err);
+ return err;
+ }
+ if (main_prog->line_info) {
+ /*
+ * Some info has already been found but has problem
+ * in the last btf_ext reloc. Must have to error out.
+ */
+ pr_warn("prog '%s': missing .BTF.ext line info.\n", prog->name);
+ return err;
+ }
+ /* Have problem loading the very first info. Ignore the rest. */
+ pr_warn("prog '%s': missing .BTF.ext line info for the main program, skipping all of .BTF.ext line info.\n",
+ prog->name);
+ }
+ return 0;
+}
+
static int cmp_relo_by_insn_idx(const void *key, const void *elem)
{
size_t insn_idx = *(const size_t *)key;
@@ -6064,13 +6136,6 @@ bpf_object__relocate_calls(struct bpf_object *obj, struct bpf_program *prog)
struct bpf_program *subprog;
int i, j, err;
- if (obj->btf_ext) {
- err = bpf_program_reloc_btf_ext(prog, obj,
- prog->section_name, 0);
- if (err)
- return err;
- }
-
/* mark all subprogs as not relocated (yet) within the context of
* current main program
*/
diff --git a/tools/lib/bpf/libbpf_common.h b/tools/lib/bpf/libbpf_common.h
index a23ae1ac27ebcdc831738f540415ee2f2b0943b1..947d8bd8a7bb63e03524bfc8d916b23674acd230 100644
--- a/tools/lib/bpf/libbpf_common.h
+++ b/tools/lib/bpf/libbpf_common.h
@@ -15,6 +15,8 @@
#define LIBBPF_API __attribute__((visibility("default")))
#endif
+#define LIBBPF_DEPRECATED(msg) __attribute__((deprecated(msg)))
+
/* Helper macro to declare and initialize libbpf options struct
*
* This dance with uninitialized declaration, followed by memset to zero,