From 917f6b7b07a46e53fa73e112d23c97d1b201a877 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Fri, 13 Dec 2019 17:43:28 -0800 Subject: [PATCH] libbpf: Add BPF_EMBED_OBJ macro for embedding BPF .o files Add a convenience macro BPF_EMBED_OBJ, which allows to embed other files (typically used to embed BPF .o files) into a hosting userspace programs. To C program it is exposed as struct bpf_embed_data, containing a pointer to raw data and its size in bytes. Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Acked-by: Martin KaFai Lau Link: https://lore.kernel.org/bpf/20191214014341.3442258-5-andriin@fb.com --- tools/lib/bpf/libbpf.h | 35 +++++++++++++++++++ .../selftests/bpf/prog_tests/attach_probe.c | 23 ++---------- 2 files changed, 38 insertions(+), 20 deletions(-) diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 2698fbcb0c79..fa803dde1f46 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -615,6 +615,41 @@ bpf_program__bpil_offs_to_addr(struct bpf_prog_info_linear *info_linear); */ LIBBPF_API int libbpf_num_possible_cpus(void); +struct bpf_embed_data { + void *data; + size_t size; +}; + +#define BPF_EMBED_OBJ_DECLARE(NAME) \ +extern struct bpf_embed_data NAME##_embed; \ +extern char NAME##_data[]; \ +extern char NAME##_data_end[]; + +#define __BPF_EMBED_OBJ(NAME, PATH, SZ, ASM_TYPE) \ +asm ( \ +" .pushsection \".rodata\", \"a\", @progbits \n" \ +" .global "#NAME"_data \n" \ +#NAME"_data: \n" \ +" .incbin \"" PATH "\" \n" \ +" .global "#NAME"_data_end \n" \ +#NAME"_data_end: \n" \ +" .global "#NAME"_embed \n" \ +" .type "#NAME"_embed, @object \n" \ +" .size "#NAME"_size, "#SZ" \n" \ +" .align 8, \n" \ +#NAME"_embed: \n" \ +" "ASM_TYPE" "#NAME"_data \n" \ +" "ASM_TYPE" "#NAME"_data_end - "#NAME"_data \n" \ +" .popsection \n" \ +); \ +BPF_EMBED_OBJ_DECLARE(NAME) + +#if __SIZEOF_POINTER__ == 4 +#define BPF_EMBED_OBJ(NAME, PATH) __BPF_EMBED_OBJ(NAME, PATH, 8, ".long") +#else +#define BPF_EMBED_OBJ(NAME, PATH) __BPF_EMBED_OBJ(NAME, PATH, 16, ".quad") +#endif + #ifdef __cplusplus } /* extern "C" */ #endif diff --git a/tools/testing/selftests/bpf/prog_tests/attach_probe.c b/tools/testing/selftests/bpf/prog_tests/attach_probe.c index a83111a32d4a..b2e7c1424b07 100644 --- a/tools/testing/selftests/bpf/prog_tests/attach_probe.c +++ b/tools/testing/selftests/bpf/prog_tests/attach_probe.c @@ -1,24 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 #include -#define EMBED_FILE(NAME, PATH) \ -asm ( \ -" .pushsection \".rodata\", \"a\", @progbits \n" \ -" .global "#NAME"_data \n" \ -#NAME"_data: \n" \ -" .incbin \"" PATH "\" \n" \ -#NAME"_data_end: \n" \ -" .global "#NAME"_size \n" \ -" .type "#NAME"_size, @object \n" \ -" .size "#NAME"_size, 4 \n" \ -" .align 4, \n" \ -#NAME"_size: \n" \ -" .int "#NAME"_data_end - "#NAME"_data \n" \ -" .popsection \n" \ -); \ -extern char NAME##_data[]; \ -extern int NAME##_size; - ssize_t get_base_addr() { size_t start; char buf[256]; @@ -39,7 +21,7 @@ ssize_t get_base_addr() { return -EINVAL; } -EMBED_FILE(probe, "test_attach_probe.o"); +BPF_EMBED_OBJ(probe, "test_attach_probe.o"); void test_attach_probe(void) { @@ -73,7 +55,8 @@ void test_attach_probe(void) uprobe_offset = (size_t)&get_base_addr - base_addr; /* open object */ - obj = bpf_object__open_mem(probe_data, probe_size, &open_opts); + obj = bpf_object__open_mem(probe_embed.data, probe_embed.size, + &open_opts); if (CHECK(IS_ERR(obj), "obj_open_mem", "err %ld\n", PTR_ERR(obj))) return; -- 2.30.2