diff options
| -rw-r--r-- | tools/lib/bpf/btf.h | 3 | ||||
| -rw-r--r-- | tools/lib/bpf/libbpf.c | 56 | ||||
| -rw-r--r-- | tools/lib/bpf/libbpf_internal.h | 2 |
3 files changed, 56 insertions, 5 deletions
diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h index dcb3f575a281..83312c34007a 100644 --- a/tools/lib/bpf/btf.h +++ b/tools/lib/bpf/btf.h @@ -395,9 +395,10 @@ btf_dump__dump_type_data(struct btf_dump *d, __u32 id, #ifndef BTF_KIND_FLOAT #define BTF_KIND_FLOAT 16 /* Floating point */ #endif -/* The kernel header switched to enums, so these two were never #defined */ +/* The kernel header switched to enums, so the following were never #defined */ #define BTF_KIND_DECL_TAG 17 /* Decl Tag */ #define BTF_KIND_TYPE_TAG 18 /* Type Tag */ +#define BTF_KIND_ENUM64 19 /* Enum for up-to 64bit values */ static inline __u16 btf_kind(const struct btf_type *t) { diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index b03165687936..a0f5aae8626b 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -2242,6 +2242,7 @@ static const char *__btf_kind_str(__u16 kind) case BTF_KIND_FLOAT: return "float"; case BTF_KIND_DECL_TAG: return "decl_tag"; case BTF_KIND_TYPE_TAG: return "type_tag"; + case BTF_KIND_ENUM64: return "enum64"; default: return "unknown"; } } @@ -2770,12 +2771,13 @@ static bool btf_needs_sanitization(struct bpf_object *obj) bool has_func = kernel_supports(obj, FEAT_BTF_FUNC); bool has_decl_tag = kernel_supports(obj, FEAT_BTF_DECL_TAG); bool has_type_tag = kernel_supports(obj, FEAT_BTF_TYPE_TAG); + bool has_enum64 = kernel_supports(obj, FEAT_BTF_ENUM64); return !has_func || !has_datasec || !has_func_global || !has_float || - !has_decl_tag || !has_type_tag; + !has_decl_tag || !has_type_tag || !has_enum64; } -static void bpf_object__sanitize_btf(struct bpf_object *obj, struct btf *btf) +static int bpf_object__sanitize_btf(struct bpf_object *obj, struct btf *btf) { bool has_func_global = kernel_supports(obj, FEAT_BTF_GLOBAL_FUNC); bool has_datasec = kernel_supports(obj, FEAT_BTF_DATASEC); @@ -2783,6 +2785,8 @@ static void bpf_object__sanitize_btf(struct bpf_object *obj, struct btf *btf) bool has_func = kernel_supports(obj, FEAT_BTF_FUNC); bool has_decl_tag = kernel_supports(obj, FEAT_BTF_DECL_TAG); bool has_type_tag = kernel_supports(obj, FEAT_BTF_TYPE_TAG); + bool has_enum64 = kernel_supports(obj, FEAT_BTF_ENUM64); + __u32 enum64_placeholder_id = 0; struct btf_type *t; int i, j, vlen; @@ -2845,8 +2849,32 @@ static void bpf_object__sanitize_btf(struct bpf_object *obj, struct btf *btf) /* replace TYPE_TAG with a CONST */ t->name_off = 0; t->info = BTF_INFO_ENC(BTF_KIND_CONST, 0, 0); - } + } else if (!has_enum64 && btf_is_enum(t)) { + /* clear the kflag */ + t->info = btf_type_info(btf_kind(t), btf_vlen(t), false); + } else if (!has_enum64 && btf_is_enum64(t)) { + /* replace ENUM64 with a union */ + struct btf_member *m; + + if (enum64_placeholder_id == 0) { + enum64_placeholder_id = btf__add_int(btf, "enum64_placeholder", 1, 0); + if (enum64_placeholder_id < 0) + return enum64_placeholder_id; + + t = (struct btf_type *)btf__type_by_id(btf, i); + } + + m = btf_members(t); + vlen = btf_vlen(t); + t->info = BTF_INFO_ENC(BTF_KIND_UNION, 0, vlen); + for (j = 0; j < vlen; j++, m++) { + m->type = enum64_placeholder_id; + m->offset = 0; + } + } } + + return 0; } static bool libbpf_needs_btf(const struct bpf_object *obj) @@ -3184,7 +3212,9 @@ static int bpf_object__sanitize_and_load_btf(struct bpf_object *obj) /* enforce 8-byte pointers for BPF-targeted BTFs */ btf__set_pointer_size(obj->btf, 8); - bpf_object__sanitize_btf(obj, kern_btf); + err = bpf_object__sanitize_btf(obj, kern_btf); + if (err) + return err; } if (obj->gen_loader) { @@ -3691,6 +3721,10 @@ static enum kcfg_type find_kcfg_type(const struct btf *btf, int id, if (strcmp(name, "libbpf_tristate")) return KCFG_UNKNOWN; return KCFG_TRISTATE; + case BTF_KIND_ENUM64: + if (strcmp(name, "libbpf_tristate")) + return KCFG_UNKNOWN; + return KCFG_TRISTATE; case BTF_KIND_ARRAY: if (btf_array(t)->nelems == 0) return KCFG_UNKNOWN; @@ -4874,6 +4908,17 @@ static int probe_kern_bpf_cookie(void) return probe_fd(ret); } +static int probe_kern_btf_enum64(void) +{ + static const char strs[] = "\0enum64"; + __u32 types[] = { + BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_ENUM64, 0, 0), 8), + }; + + return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), + strs, sizeof(strs))); +} + enum kern_feature_result { FEAT_UNKNOWN = 0, FEAT_SUPPORTED = 1, @@ -4939,6 +4984,9 @@ static struct kern_feature_desc { [FEAT_BPF_COOKIE] = { "BPF cookie support", probe_kern_bpf_cookie, }, + [FEAT_BTF_ENUM64] = { + "BTF_KIND_ENUM64 support", probe_kern_btf_enum64, + }, }; bool kernel_supports(const struct bpf_object *obj, enum kern_feature_id feat_id) diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h index ef5d975078e5..a1ad145ffa74 100644 --- a/tools/lib/bpf/libbpf_internal.h +++ b/tools/lib/bpf/libbpf_internal.h @@ -351,6 +351,8 @@ enum kern_feature_id { FEAT_MEMCG_ACCOUNT, /* BPF cookie (bpf_get_attach_cookie() BPF helper) support */ FEAT_BPF_COOKIE, + /* BTF_KIND_ENUM64 support and BTF_KIND_ENUM kflag support */ + FEAT_BTF_ENUM64, __FEAT_CNT, }; |