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-rw-r--r--tools/bpf/bpftool/btf.c148
1 files changed, 120 insertions, 28 deletions
diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c
index 015d2758f826..68a70ac03c80 100644
--- a/tools/bpf/bpftool/btf.c
+++ b/tools/bpf/bpftool/btf.c
@@ -39,11 +39,8 @@ static const char * const btf_kind_str[NR_BTF_KINDS] = {
[BTF_KIND_DATASEC] = "DATASEC",
[BTF_KIND_FLOAT] = "FLOAT",
[BTF_KIND_DECL_TAG] = "DECL_TAG",
-};
-
-struct btf_attach_point {
- __u32 obj_id;
- __u32 btf_id;
+ [BTF_KIND_TYPE_TAG] = "TYPE_TAG",
+ [BTF_KIND_ENUM64] = "ENUM64",
};
static const char *btf_int_enc_str(__u8 encoding)
@@ -142,6 +139,7 @@ static int dump_btf_type(const struct btf *btf, __u32 id,
case BTF_KIND_VOLATILE:
case BTF_KIND_RESTRICT:
case BTF_KIND_TYPEDEF:
+ case BTF_KIND_TYPE_TAG:
if (json_output)
jsonw_uint_field(w, "type_id", t->type);
else
@@ -210,26 +208,76 @@ static int dump_btf_type(const struct btf *btf, __u32 id,
case BTF_KIND_ENUM: {
const struct btf_enum *v = (const void *)(t + 1);
__u16 vlen = BTF_INFO_VLEN(t->info);
+ const char *encoding;
int i;
+ encoding = btf_kflag(t) ? "SIGNED" : "UNSIGNED";
if (json_output) {
+ jsonw_string_field(w, "encoding", encoding);
jsonw_uint_field(w, "size", t->size);
jsonw_uint_field(w, "vlen", vlen);
jsonw_name(w, "values");
jsonw_start_array(w);
} else {
- printf(" size=%u vlen=%u", t->size, vlen);
+ printf(" encoding=%s size=%u vlen=%u", encoding, t->size, vlen);
+ }
+ for (i = 0; i < vlen; i++, v++) {
+ const char *name = btf_str(btf, v->name_off);
+
+ if (json_output) {
+ jsonw_start_object(w);
+ jsonw_string_field(w, "name", name);
+ if (btf_kflag(t))
+ jsonw_int_field(w, "val", v->val);
+ else
+ jsonw_uint_field(w, "val", v->val);
+ jsonw_end_object(w);
+ } else {
+ if (btf_kflag(t))
+ printf("\n\t'%s' val=%d", name, v->val);
+ else
+ printf("\n\t'%s' val=%u", name, v->val);
+ }
+ }
+ if (json_output)
+ jsonw_end_array(w);
+ break;
+ }
+ case BTF_KIND_ENUM64: {
+ const struct btf_enum64 *v = btf_enum64(t);
+ __u16 vlen = btf_vlen(t);
+ const char *encoding;
+ int i;
+
+ encoding = btf_kflag(t) ? "SIGNED" : "UNSIGNED";
+ if (json_output) {
+ jsonw_string_field(w, "encoding", encoding);
+ jsonw_uint_field(w, "size", t->size);
+ jsonw_uint_field(w, "vlen", vlen);
+ jsonw_name(w, "values");
+ jsonw_start_array(w);
+ } else {
+ printf(" encoding=%s size=%u vlen=%u", encoding, t->size, vlen);
}
for (i = 0; i < vlen; i++, v++) {
const char *name = btf_str(btf, v->name_off);
+ __u64 val = ((__u64)v->val_hi32 << 32) | v->val_lo32;
if (json_output) {
jsonw_start_object(w);
jsonw_string_field(w, "name", name);
- jsonw_uint_field(w, "val", v->val);
+ if (btf_kflag(t))
+ jsonw_int_field(w, "val", val);
+ else
+ jsonw_uint_field(w, "val", val);
jsonw_end_object(w);
} else {
- printf("\n\t'%s' val=%u", name, v->val);
+ if (btf_kflag(t))
+ printf("\n\t'%s' val=%lldLL", name,
+ (unsigned long long)val);
+ else
+ printf("\n\t'%s' val=%lluULL", name,
+ (unsigned long long)val);
}
}
if (json_output)
@@ -418,9 +466,10 @@ static int dump_btf_c(const struct btf *btf,
struct btf_dump *d;
int err = 0, i;
- d = btf_dump__new(btf, NULL, NULL, btf_dump_printf);
- if (IS_ERR(d))
- return PTR_ERR(d);
+ d = btf_dump__new(btf, btf_dump_printf, NULL, NULL);
+ err = libbpf_get_error(d);
+ if (err)
+ return err;
printf("#ifndef __VMLINUX_H__\n");
printf("#define __VMLINUX_H__\n");
@@ -456,6 +505,51 @@ done:
return err;
}
+static const char sysfs_vmlinux[] = "/sys/kernel/btf/vmlinux";
+
+static struct btf *get_vmlinux_btf_from_sysfs(void)
+{
+ struct btf *base;
+
+ base = btf__parse(sysfs_vmlinux, NULL);
+ if (libbpf_get_error(base)) {
+ p_err("failed to parse vmlinux BTF at '%s': %ld\n",
+ sysfs_vmlinux, libbpf_get_error(base));
+ base = NULL;
+ }
+
+ return base;
+}
+
+#define BTF_NAME_BUFF_LEN 64
+
+static bool btf_is_kernel_module(__u32 btf_id)
+{
+ struct bpf_btf_info btf_info = {};
+ char btf_name[BTF_NAME_BUFF_LEN];
+ int btf_fd;
+ __u32 len;
+ int err;
+
+ btf_fd = bpf_btf_get_fd_by_id(btf_id);
+ if (btf_fd < 0) {
+ p_err("can't get BTF object by id (%u): %s", btf_id, strerror(errno));
+ return false;
+ }
+
+ len = sizeof(btf_info);
+ btf_info.name = ptr_to_u64(btf_name);
+ btf_info.name_len = sizeof(btf_name);
+ err = bpf_obj_get_info_by_fd(btf_fd, &btf_info, &len);
+ close(btf_fd);
+ if (err) {
+ p_err("can't get BTF (ID %u) object info: %s", btf_id, strerror(errno));
+ return false;
+ }
+
+ return btf_info.kernel_btf && strncmp(btf_name, "vmlinux", sizeof(btf_name)) != 0;
+}
+
static int do_dump(int argc, char **argv)
{
struct btf *btf = NULL, *base = NULL;
@@ -533,25 +627,17 @@ static int do_dump(int argc, char **argv)
NEXT_ARG();
} else if (is_prefix(src, "file")) {
const char sysfs_prefix[] = "/sys/kernel/btf/";
- const char sysfs_vmlinux[] = "/sys/kernel/btf/vmlinux";
if (!base_btf &&
strncmp(*argv, sysfs_prefix, sizeof(sysfs_prefix) - 1) == 0 &&
- strcmp(*argv, sysfs_vmlinux) != 0) {
- base = btf__parse(sysfs_vmlinux, NULL);
- if (libbpf_get_error(base)) {
- p_err("failed to parse vmlinux BTF at '%s': %ld\n",
- sysfs_vmlinux, libbpf_get_error(base));
- base = NULL;
- }
- }
+ strcmp(*argv, sysfs_vmlinux) != 0)
+ base = get_vmlinux_btf_from_sysfs();
btf = btf__parse_split(*argv, base ?: base_btf);
- if (IS_ERR(btf)) {
- err = -PTR_ERR(btf);
- btf = NULL;
+ err = libbpf_get_error(btf);
+ if (!btf) {
p_err("failed to load BTF from %s: %s",
- *argv, strerror(err));
+ *argv, strerror(errno));
goto done;
}
NEXT_ARG();
@@ -588,10 +674,16 @@ static int do_dump(int argc, char **argv)
}
if (!btf) {
+ if (!base_btf && btf_is_kernel_module(btf_id)) {
+ p_info("Warning: valid base BTF was not specified with -B option, falling back to standard base BTF (%s)",
+ sysfs_vmlinux);
+ base_btf = get_vmlinux_btf_from_sysfs();
+ }
+
btf = btf__load_from_kernel_by_id_split(btf_id, base_btf);
err = libbpf_get_error(btf);
- if (err) {
- p_err("get btf by id (%u): %s", btf_id, strerror(err));
+ if (!btf) {
+ p_err("get btf by id (%u): %s", btf_id, strerror(errno));
goto done;
}
}
@@ -727,7 +819,7 @@ build_btf_type_table(struct hashmap *tab, enum bpf_obj_type type,
u32_as_hash_field(id));
if (err) {
p_err("failed to append entry to hashmap for BTF ID %u, object ID %u: %s",
- btf_id, id, strerror(errno));
+ btf_id, id, strerror(-err));
goto err_free;
}
}
@@ -899,7 +991,7 @@ static int do_show(int argc, char **argv)
equal_fn_for_key_as_id, NULL);
btf_map_table = hashmap__new(hash_fn_for_key_as_id,
equal_fn_for_key_as_id, NULL);
- if (!btf_prog_table || !btf_map_table) {
+ if (IS_ERR(btf_prog_table) || IS_ERR(btf_map_table)) {
hashmap__free(btf_prog_table);
hashmap__free(btf_map_table);
if (fd >= 0)
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