diff mbox series

[bpf-next,v5,10/17] libbpf: Add enum64 relocation support

Message ID 20220607062647.3721719-1-yhs@fb.com (mailing list archive)
State Accepted
Commit 23b2a3a8f63a9dc14ad0c7a63098e0b3575b1173
Delegated to: BPF
Headers show
Series bpf: Add 64bit enum value support | expand

Checks

Context Check Description
bpf/vmtest-bpf-next-VM_Test-3 fail Logs for Kernel LATEST on z15 with gcc
bpf/vmtest-bpf-next-PR fail PR summary
bpf/vmtest-bpf-next-VM_Test-1 fail Logs for Kernel LATEST on ubuntu-latest with gcc
bpf/vmtest-bpf-next-VM_Test-2 fail Logs for Kernel LATEST on ubuntu-latest with llvm-15
netdev/tree_selection success Clearly marked for bpf-next, async
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count fail Series longer than 15 patches (and no cover letter)
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 2 this patch: 2
netdev/cc_maintainers warning 5 maintainers not CCed: netdev@vger.kernel.org songliubraving@fb.com john.fastabend@gmail.com kafai@fb.com kpsingh@kernel.org
netdev/build_clang success Errors and warnings before: 6 this patch: 6
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 2 this patch: 2
netdev/checkpatch warning WARNING: line length of 82 exceeds 80 columns WARNING: line length of 83 exceeds 80 columns WARNING: line length of 86 exceeds 80 columns WARNING: line length of 88 exceeds 80 columns WARNING: line length of 90 exceeds 80 columns
netdev/kdoc success Errors and warnings before: 12 this patch: 12
netdev/source_inline success Was 0 now: 0

Commit Message

Yonghong Song June 7, 2022, 6:26 a.m. UTC
The enum64 relocation support is added. The bpf local type
could be either enum or enum64 and the remote type could be
either enum or enum64 too. The all combinations of local enum/enum64
and remote enum/enum64 are supported.

Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Yonghong Song <yhs@fb.com>
---
 tools/lib/bpf/btf.h       |  7 +++++
 tools/lib/bpf/libbpf.c    |  7 ++---
 tools/lib/bpf/relo_core.c | 54 +++++++++++++++++++++++++++------------
 3 files changed, 48 insertions(+), 20 deletions(-)
diff mbox series

Patch

diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h
index 83312c34007a..9fb416eb5644 100644
--- a/tools/lib/bpf/btf.h
+++ b/tools/lib/bpf/btf.h
@@ -537,6 +537,13 @@  static inline bool btf_is_any_enum(const struct btf_type *t)
 	return btf_is_enum(t) || btf_is_enum64(t);
 }
 
+static inline bool btf_kind_core_compat(const struct btf_type *t1,
+					const struct btf_type *t2)
+{
+	return btf_kind(t1) == btf_kind(t2) ||
+	       (btf_is_any_enum(t1) && btf_is_any_enum(t2));
+}
+
 static inline __u8 btf_int_encoding(const struct btf_type *t)
 {
 	return BTF_INT_ENCODING(*(__u32 *)(t + 1));
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index a0f5aae8626b..ed3cf0911b98 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -5524,7 +5524,7 @@  int bpf_core_add_cands(struct bpf_core_cand *local_cand,
 	n = btf__type_cnt(targ_btf);
 	for (i = targ_start_id; i < n; i++) {
 		t = btf__type_by_id(targ_btf, i);
-		if (btf_kind(t) != btf_kind(local_t))
+		if (!btf_kind_core_compat(t, local_t))
 			continue;
 
 		targ_name = btf__name_by_offset(targ_btf, t->name_off);
@@ -5738,7 +5738,7 @@  int bpf_core_types_are_compat(const struct btf *local_btf, __u32 local_id,
 	/* caller made sure that names match (ignoring flavor suffix) */
 	local_type = btf__type_by_id(local_btf, local_id);
 	targ_type = btf__type_by_id(targ_btf, targ_id);
-	if (btf_kind(local_type) != btf_kind(targ_type))
+	if (!btf_kind_core_compat(local_type, targ_type))
 		return 0;
 
 recur:
@@ -5751,7 +5751,7 @@  int bpf_core_types_are_compat(const struct btf *local_btf, __u32 local_id,
 	if (!local_type || !targ_type)
 		return -EINVAL;
 
-	if (btf_kind(local_type) != btf_kind(targ_type))
+	if (!btf_kind_core_compat(local_type, targ_type))
 		return 0;
 
 	switch (btf_kind(local_type)) {
@@ -5759,6 +5759,7 @@  int bpf_core_types_are_compat(const struct btf *local_btf, __u32 local_id,
 	case BTF_KIND_STRUCT:
 	case BTF_KIND_UNION:
 	case BTF_KIND_ENUM:
+	case BTF_KIND_ENUM64:
 	case BTF_KIND_FWD:
 		return 1;
 	case BTF_KIND_INT:
diff --git a/tools/lib/bpf/relo_core.c b/tools/lib/bpf/relo_core.c
index 073a54ed7432..6ad3c3891a9a 100644
--- a/tools/lib/bpf/relo_core.c
+++ b/tools/lib/bpf/relo_core.c
@@ -186,7 +186,7 @@  int bpf_core_parse_spec(const char *prog_name, const struct btf *btf,
 	struct bpf_core_accessor *acc;
 	const struct btf_type *t;
 	const char *name, *spec_str;
-	__u32 id;
+	__u32 id, name_off;
 	__s64 sz;
 
 	spec_str = btf__name_by_offset(btf, relo->access_str_off);
@@ -231,11 +231,13 @@  int bpf_core_parse_spec(const char *prog_name, const struct btf *btf,
 	spec->len++;
 
 	if (core_relo_is_enumval_based(relo->kind)) {
-		if (!btf_is_enum(t) || spec->raw_len > 1 || access_idx >= btf_vlen(t))
+		if (!btf_is_any_enum(t) || spec->raw_len > 1 || access_idx >= btf_vlen(t))
 			return -EINVAL;
 
 		/* record enumerator name in a first accessor */
-		acc->name = btf__name_by_offset(btf, btf_enum(t)[access_idx].name_off);
+		name_off = btf_is_enum(t) ? btf_enum(t)[access_idx].name_off
+					  : btf_enum64(t)[access_idx].name_off;
+		acc->name = btf__name_by_offset(btf, name_off);
 		return 0;
 	}
 
@@ -340,7 +342,7 @@  static int bpf_core_fields_are_compat(const struct btf *local_btf,
 
 	if (btf_is_composite(local_type) && btf_is_composite(targ_type))
 		return 1;
-	if (btf_kind(local_type) != btf_kind(targ_type))
+	if (!btf_kind_core_compat(local_type, targ_type))
 		return 0;
 
 	switch (btf_kind(local_type)) {
@@ -348,6 +350,7 @@  static int bpf_core_fields_are_compat(const struct btf *local_btf,
 	case BTF_KIND_FLOAT:
 		return 1;
 	case BTF_KIND_FWD:
+	case BTF_KIND_ENUM64:
 	case BTF_KIND_ENUM: {
 		const char *local_name, *targ_name;
 		size_t local_len, targ_len;
@@ -477,6 +480,7 @@  static int bpf_core_spec_match(struct bpf_core_spec *local_spec,
 	const struct bpf_core_accessor *local_acc;
 	struct bpf_core_accessor *targ_acc;
 	int i, sz, matched;
+	__u32 name_off;
 
 	memset(targ_spec, 0, sizeof(*targ_spec));
 	targ_spec->btf = targ_btf;
@@ -494,18 +498,22 @@  static int bpf_core_spec_match(struct bpf_core_spec *local_spec,
 
 	if (core_relo_is_enumval_based(local_spec->relo_kind)) {
 		size_t local_essent_len, targ_essent_len;
-		const struct btf_enum *e;
 		const char *targ_name;
 
 		/* has to resolve to an enum */
 		targ_type = skip_mods_and_typedefs(targ_spec->btf, targ_id, &targ_id);
-		if (!btf_is_enum(targ_type))
+		if (!btf_is_any_enum(targ_type))
 			return 0;
 
 		local_essent_len = bpf_core_essential_name_len(local_acc->name);
 
-		for (i = 0, e = btf_enum(targ_type); i < btf_vlen(targ_type); i++, e++) {
-			targ_name = btf__name_by_offset(targ_spec->btf, e->name_off);
+		for (i = 0; i < btf_vlen(targ_type); i++) {
+			if (btf_is_enum(targ_type))
+				name_off = btf_enum(targ_type)[i].name_off;
+			else
+				name_off = btf_enum64(targ_type)[i].name_off;
+
+			targ_name = btf__name_by_offset(targ_spec->btf, name_off);
 			targ_essent_len = bpf_core_essential_name_len(targ_name);
 			if (targ_essent_len != local_essent_len)
 				continue;
@@ -680,8 +688,7 @@  static int bpf_core_calc_field_relo(const char *prog_name,
 		*val = byte_sz;
 		break;
 	case BPF_CORE_FIELD_SIGNED:
-		/* enums will be assumed unsigned */
-		*val = btf_is_enum(mt) ||
+		*val = (btf_is_any_enum(mt) && BTF_INFO_KFLAG(mt->info)) ||
 		       (btf_int_encoding(mt) & BTF_INT_SIGNED);
 		if (validate)
 			*validate = true; /* signedness is never ambiguous */
@@ -754,7 +761,6 @@  static int bpf_core_calc_enumval_relo(const struct bpf_core_relo *relo,
 				      __u64 *val)
 {
 	const struct btf_type *t;
-	const struct btf_enum *e;
 
 	switch (relo->kind) {
 	case BPF_CORE_ENUMVAL_EXISTS:
@@ -764,8 +770,10 @@  static int bpf_core_calc_enumval_relo(const struct bpf_core_relo *relo,
 		if (!spec)
 			return -EUCLEAN; /* request instruction poisoning */
 		t = btf_type_by_id(spec->btf, spec->spec[0].type_id);
-		e = btf_enum(t) + spec->spec[0].idx;
-		*val = e->val;
+		if (btf_is_enum(t))
+			*val = btf_enum(t)[spec->spec[0].idx].val;
+		else
+			*val = btf_enum64_value(btf_enum64(t) + spec->spec[0].idx);
 		break;
 	default:
 		return -EOPNOTSUPP;
@@ -1060,7 +1068,6 @@  int bpf_core_patch_insn(const char *prog_name, struct bpf_insn *insn,
 int bpf_core_format_spec(char *buf, size_t buf_sz, const struct bpf_core_spec *spec)
 {
 	const struct btf_type *t;
-	const struct btf_enum *e;
 	const char *s;
 	__u32 type_id;
 	int i, len = 0;
@@ -1089,10 +1096,23 @@  int bpf_core_format_spec(char *buf, size_t buf_sz, const struct bpf_core_spec *s
 
 	if (core_relo_is_enumval_based(spec->relo_kind)) {
 		t = skip_mods_and_typedefs(spec->btf, type_id, NULL);
-		e = btf_enum(t) + spec->raw_spec[0];
-		s = btf__name_by_offset(spec->btf, e->name_off);
+		if (btf_is_enum(t)) {
+			const struct btf_enum *e;
+			const char *fmt_str;
+
+			e = btf_enum(t) + spec->raw_spec[0];
+			s = btf__name_by_offset(spec->btf, e->name_off);
+			fmt_str = BTF_INFO_KFLAG(t->info) ? "::%s = %d" : "::%s = %u";
+			append_buf(fmt_str, s, e->val);
+		} else {
+			const struct btf_enum64 *e;
+			const char *fmt_str;
 
-		append_buf("::%s = %u", s, e->val);
+			e = btf_enum64(t) + spec->raw_spec[0];
+			s = btf__name_by_offset(spec->btf, e->name_off);
+			fmt_str = BTF_INFO_KFLAG(t->info) ? "::%s = %lld" : "::%s = %llu";
+			append_buf(fmt_str, s, (unsigned long long)btf_enum64_value(e));
+		}
 		return len;
 	}