From e2fa0156a434c140998aa16ecad329e4bc19f263 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Thu, 13 May 2021 17:36:15 -0700 Subject: [PATCH] libbpf: Preliminary support for fd_idx Prep libbpf to use FD_IDX kernel feature when generating loader program. Signed-off-by: Alexei Starovoitov Signed-off-by: Daniel Borkmann Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20210514003623.28033-14-alexei.starovoitov@gmail.com --- tools/lib/bpf/libbpf.c | 31 +++++++++++++++++++++++++------ 1 file changed, 25 insertions(+), 6 deletions(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 29e26fabe2ee..f398ca83167e 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -412,6 +412,8 @@ struct module_btf { int fd; }; +struct bpf_gen; + struct bpf_object { char name[BPF_OBJ_NAME_LEN]; char license[64]; @@ -432,6 +434,8 @@ struct bpf_object { bool loaded; bool has_subcalls; + struct bpf_gen *gen_loader; + /* * Information when doing elf related work. Only valid if fd * is valid. @@ -6388,19 +6392,34 @@ bpf_object__relocate_data(struct bpf_object *obj, struct bpf_program *prog) switch (relo->type) { case RELO_LD64: - insn[0].src_reg = BPF_PSEUDO_MAP_FD; - insn[0].imm = obj->maps[relo->map_idx].fd; + if (obj->gen_loader) { + insn[0].src_reg = BPF_PSEUDO_MAP_IDX; + insn[0].imm = relo->map_idx; + } else { + insn[0].src_reg = BPF_PSEUDO_MAP_FD; + insn[0].imm = obj->maps[relo->map_idx].fd; + } break; case RELO_DATA: - insn[0].src_reg = BPF_PSEUDO_MAP_VALUE; insn[1].imm = insn[0].imm + relo->sym_off; - insn[0].imm = obj->maps[relo->map_idx].fd; + if (obj->gen_loader) { + insn[0].src_reg = BPF_PSEUDO_MAP_IDX_VALUE; + insn[0].imm = relo->map_idx; + } else { + insn[0].src_reg = BPF_PSEUDO_MAP_VALUE; + insn[0].imm = obj->maps[relo->map_idx].fd; + } break; case RELO_EXTERN_VAR: ext = &obj->externs[relo->sym_off]; if (ext->type == EXT_KCFG) { - insn[0].src_reg = BPF_PSEUDO_MAP_VALUE; - insn[0].imm = obj->maps[obj->kconfig_map_idx].fd; + if (obj->gen_loader) { + insn[0].src_reg = BPF_PSEUDO_MAP_IDX_VALUE; + insn[0].imm = obj->kconfig_map_idx; + } else { + insn[0].src_reg = BPF_PSEUDO_MAP_VALUE; + insn[0].imm = obj->maps[obj->kconfig_map_idx].fd; + } insn[1].imm = ext->kcfg.data_off; } else /* EXT_KSYM */ { if (ext->ksym.type_id) { /* typed ksyms */ -- 2.11.0