Commit 9ca1f56a authored by Alexei Starovoitov's avatar Alexei Starovoitov Committed by Daniel Borkmann
Browse files

libbpf: Add bpf_object pointer to kernel_supports(). 



Add a pointer to 'struct bpf_object' to kernel_supports() helper.
It will be used in the next patch.
No functional changes.

Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Acked-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210514003623.28033-13-alexei.starovoitov@gmail.com
parent b1268826

tools/lib/bpf/libbpf.c

+22 −22
Original line number Diff line number Diff line
@@ -178,7 +178,7 @@ enum kern_feature_id { 
	__FEAT_CNT,

};



static bool kernel_supports(enum kern_feature_id feat_id);

static bool kernel_supports(const struct bpf_object *obj, enum kern_feature_id feat_id);



enum reloc_type {

	RELO_LD64,
@@ -2463,20 +2463,20 @@ static bool section_have_execinstr(struct bpf_object *obj, int idx) 


static bool btf_needs_sanitization(struct bpf_object *obj)

{

	bool has_func_global = kernel_supports(FEAT_BTF_GLOBAL_FUNC);

	bool has_datasec = kernel_supports(FEAT_BTF_DATASEC);

	bool has_float = kernel_supports(FEAT_BTF_FLOAT);

	bool has_func = kernel_supports(FEAT_BTF_FUNC);

	bool has_func_global = kernel_supports(obj, FEAT_BTF_GLOBAL_FUNC);

	bool has_datasec = kernel_supports(obj, FEAT_BTF_DATASEC);

	bool has_float = kernel_supports(obj, FEAT_BTF_FLOAT);

	bool has_func = kernel_supports(obj, FEAT_BTF_FUNC);



	return !has_func || !has_datasec || !has_func_global || !has_float;

}



static void bpf_object__sanitize_btf(struct bpf_object *obj, struct btf *btf)

{

	bool has_func_global = kernel_supports(FEAT_BTF_GLOBAL_FUNC);

	bool has_datasec = kernel_supports(FEAT_BTF_DATASEC);

	bool has_float = kernel_supports(FEAT_BTF_FLOAT);

	bool has_func = kernel_supports(FEAT_BTF_FUNC);

	bool has_func_global = kernel_supports(obj, FEAT_BTF_GLOBAL_FUNC);

	bool has_datasec = kernel_supports(obj, FEAT_BTF_DATASEC);

	bool has_float = kernel_supports(obj, FEAT_BTF_FLOAT);

	bool has_func = kernel_supports(obj, FEAT_BTF_FUNC);

	struct btf_type *t;

	int i, j, vlen;
@@ -2682,7 +2682,7 @@ static int bpf_object__sanitize_and_load_btf(struct bpf_object *obj) 
	if (!obj->btf)

		return 0;



	if (!kernel_supports(FEAT_BTF)) {

	if (!kernel_supports(obj, FEAT_BTF)) {

		if (kernel_needs_btf(obj)) {

			err = -EOPNOTSUPP;

			goto report;
@@ -4310,7 +4310,7 @@ static struct kern_feature_desc { 
	},

};



static bool kernel_supports(enum kern_feature_id feat_id)

static bool kernel_supports(const struct bpf_object *obj, enum kern_feature_id feat_id)

{

	struct kern_feature_desc *feat = &feature_probes[feat_id];

	int ret;
@@ -4429,7 +4429,7 @@ static int bpf_object__create_map(struct bpf_object *obj, struct bpf_map *map) 


	memset(&create_attr, 0, sizeof(create_attr));



	if (kernel_supports(FEAT_PROG_NAME))

	if (kernel_supports(obj, FEAT_PROG_NAME))

		create_attr.name = map->name;

	create_attr.map_ifindex = map->map_ifindex;

	create_attr.map_type = def->type;
@@ -4994,7 +4994,7 @@ static int load_module_btfs(struct bpf_object *obj) 
	obj->btf_modules_loaded = true;



	/* kernel too old to support module BTFs */

	if (!kernel_supports(FEAT_MODULE_BTF))

	if (!kernel_supports(obj, FEAT_MODULE_BTF))

		return 0;



	while (true) {
@@ -6518,7 +6518,7 @@ reloc_prog_func_and_line_info(const struct bpf_object *obj, 
	/* 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))

	if (!obj->btf_ext || !kernel_supports(obj, FEAT_BTF_FUNC))

		return 0;



	/* only attempt func info relocation if main program's func_info
@@ -7126,12 +7126,12 @@ static int bpf_object__sanitize_prog(struct bpf_object *obj, struct bpf_program 
		switch (func_id) {

		case BPF_FUNC_probe_read_kernel:

		case BPF_FUNC_probe_read_user:

			if (!kernel_supports(FEAT_PROBE_READ_KERN))

			if (!kernel_supports(obj, FEAT_PROBE_READ_KERN))

				insn->imm = BPF_FUNC_probe_read;

			break;

		case BPF_FUNC_probe_read_kernel_str:

		case BPF_FUNC_probe_read_user_str:

			if (!kernel_supports(FEAT_PROBE_READ_KERN))

			if (!kernel_supports(obj, FEAT_PROBE_READ_KERN))

				insn->imm = BPF_FUNC_probe_read_str;

			break;

		default:
@@ -7166,12 +7166,12 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt, 


	load_attr.prog_type = prog->type;

	/* old kernels might not support specifying expected_attach_type */

	if (!kernel_supports(FEAT_EXP_ATTACH_TYPE) && prog->sec_def &&

	if (!kernel_supports(prog->obj, FEAT_EXP_ATTACH_TYPE) && prog->sec_def &&

	    prog->sec_def->is_exp_attach_type_optional)

		load_attr.expected_attach_type = 0;

	else

		load_attr.expected_attach_type = prog->expected_attach_type;

	if (kernel_supports(FEAT_PROG_NAME))

	if (kernel_supports(prog->obj, FEAT_PROG_NAME))

		load_attr.name = prog->name;

	load_attr.insns = insns;

	load_attr.insn_cnt = insns_cnt;
@@ -7187,7 +7187,7 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt, 


	/* specify func_info/line_info only if kernel supports them */

	btf_fd = bpf_object__btf_fd(prog->obj);

	if (btf_fd >= 0 && kernel_supports(FEAT_BTF_FUNC)) {

	if (btf_fd >= 0 && kernel_supports(prog->obj, FEAT_BTF_FUNC)) {

		load_attr.prog_btf_fd = btf_fd;

		load_attr.func_info = prog->func_info;

		load_attr.func_info_rec_size = prog->func_info_rec_size;
@@ -7217,7 +7217,7 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt, 
			pr_debug("verifier log:\n%s", log_buf);



		if (prog->obj->rodata_map_idx >= 0 &&

		    kernel_supports(FEAT_PROG_BIND_MAP)) {

		    kernel_supports(prog->obj, FEAT_PROG_BIND_MAP)) {

			struct bpf_map *rodata_map =

				&prog->obj->maps[prog->obj->rodata_map_idx];
@@ -7575,11 +7575,11 @@ static int bpf_object__sanitize_maps(struct bpf_object *obj) 
	bpf_object__for_each_map(m, obj) {

		if (!bpf_map__is_internal(m))

			continue;

		if (!kernel_supports(FEAT_GLOBAL_DATA)) {

		if (!kernel_supports(obj, FEAT_GLOBAL_DATA)) {

			pr_warn("kernel doesn't support global data\n");

			return -ENOTSUP;

		}

		if (!kernel_supports(FEAT_ARRAY_MMAP))

		if (!kernel_supports(obj, FEAT_ARRAY_MMAP))

			m->def.map_flags ^= BPF_F_MMAPABLE;

	}