bpf: Rename BTF_KIND_TAG to BTF_KIND_DECL_TAG

Patch set [1] introduced BTF_KIND_TAG to allow tagging
declarations for struct/union, struct/union field, var, func
and func arguments and these tags will be encoded into
dwarf. They are also encoded to btf by llvm for the bpf target.

After BTF_KIND_TAG is introduced, we intended to use it
for kernel __user attributes. But kernel __user is actually
a type attribute. Upstream and internal discussion showed
it is not a good idea to mix declaration attribute and
type attribute. So we proposed to introduce btf_type_tag
as a type attribute and existing btf_tag renamed to
btf_decl_tag ([2]).

This patch renamed BTF_KIND_TAG to BTF_KIND_DECL_TAG and some
other declarations with *_tag to *_decl_tag to make it clear
the tag is for declaration. In the future, BTF_KIND_TYPE_TAG
might be introduced per [3].

 [1] https://lore.kernel.org/bpf/20210914223004.244411-1-yhs@fb.com/
 [2] https://reviews.llvm.org/D111588
 [3] https://reviews.llvm.org/D111199

Fixes: b5ea834dde6b ("bpf: Support for new btf kind BTF_KIND_TAG")
Fixes: 5b84bd10363e ("libbpf: Add support for BTF_KIND_TAG")
Fixes: 5c07f2fec003 ("bpftool: Add support for BTF_KIND_TAG")
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211012164838.3345699-1-yhs@fb.com

1 files changed, 22 insertions, 22 deletions

diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 2ebffb9f57eb..9059053088b9 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -281,7 +281,7 @@ static const char * const btf_kind_str[NR_BTF_KINDS] = {
 	[BTF_KIND_VAR]		= "VAR",
 	[BTF_KIND_DATASEC]	= "DATASEC",
 	[BTF_KIND_FLOAT]	= "FLOAT",
-	[BTF_KIND_TAG]		= "TAG",
+	[BTF_KIND_DECL_TAG]	= "DECL_TAG",
 };
 
 const char *btf_type_str(const struct btf_type *t)
@@ -460,12 +460,12 @@ static bool btf_type_is_datasec(const struct btf_type *t)
 	return BTF_INFO_KIND(t->info) == BTF_KIND_DATASEC;
 }
 
-static bool btf_type_is_tag(const struct btf_type *t)
+static bool btf_type_is_decl_tag(const struct btf_type *t)
 {
-	return BTF_INFO_KIND(t->info) == BTF_KIND_TAG;
+	return BTF_INFO_KIND(t->info) == BTF_KIND_DECL_TAG;
 }
 
-static bool btf_type_is_tag_target(const struct btf_type *t)
+static bool btf_type_is_decl_tag_target(const struct btf_type *t)
 {
 	return btf_type_is_func(t) || btf_type_is_struct(t) ||
 	       btf_type_is_var(t);
@@ -549,7 +549,7 @@ const struct btf_type *btf_type_resolve_func_ptr(const struct btf *btf,
 static bool btf_type_is_resolve_source_only(const struct btf_type *t)
 {
 	return btf_type_is_var(t) ||
-	       btf_type_is_tag(t) ||
+	       btf_type_is_decl_tag(t) ||
 	       btf_type_is_datasec(t);
 }
 
@@ -576,7 +576,7 @@ static bool btf_type_needs_resolve(const struct btf_type *t)
 	       btf_type_is_struct(t) ||
 	       btf_type_is_array(t) ||
 	       btf_type_is_var(t) ||
-	       btf_type_is_tag(t) ||
+	       btf_type_is_decl_tag(t) ||
 	       btf_type_is_datasec(t);
 }
 
@@ -630,9 +630,9 @@ static const struct btf_var *btf_type_var(const struct btf_type *t)
 	return (const struct btf_var *)(t + 1);
 }
 
-static const struct btf_tag *btf_type_tag(const struct btf_type *t)
+static const struct btf_decl_tag *btf_type_decl_tag(const struct btf_type *t)
 {
-	return (const struct btf_tag *)(t + 1);
+	return (const struct btf_decl_tag *)(t + 1);
 }
 
 static const struct btf_kind_operations *btf_type_ops(const struct btf_type *t)
@@ -3820,11 +3820,11 @@ static const struct btf_kind_operations float_ops = {
 	.show = btf_df_show,
 };
 
-static s32 btf_tag_check_meta(struct btf_verifier_env *env,
+static s32 btf_decl_tag_check_meta(struct btf_verifier_env *env,
 			      const struct btf_type *t,
 			      u32 meta_left)
 {
-	const struct btf_tag *tag;
+	const struct btf_decl_tag *tag;
 	u32 meta_needed = sizeof(*tag);
 	s32 component_idx;
 	const char *value;
@@ -3852,7 +3852,7 @@ static s32 btf_tag_check_meta(struct btf_verifier_env *env,
 		return -EINVAL;
 	}
 
-	component_idx = btf_type_tag(t)->component_idx;
+	component_idx = btf_type_decl_tag(t)->component_idx;
 	if (component_idx < -1) {
 		btf_verifier_log_type(env, t, "Invalid component_idx");
 		return -EINVAL;
@@ -3863,7 +3863,7 @@ static s32 btf_tag_check_meta(struct btf_verifier_env *env,
 	return meta_needed;
 }
 
-static int btf_tag_resolve(struct btf_verifier_env *env,
+static int btf_decl_tag_resolve(struct btf_verifier_env *env,
 			   const struct resolve_vertex *v)
 {
 	const struct btf_type *next_type;
@@ -3874,7 +3874,7 @@ static int btf_tag_resolve(struct btf_verifier_env *env,
 	u32 vlen;
 
 	next_type = btf_type_by_id(btf, next_type_id);
-	if (!next_type || !btf_type_is_tag_target(next_type)) {
+	if (!next_type || !btf_type_is_decl_tag_target(next_type)) {
 		btf_verifier_log_type(env, v->t, "Invalid type_id");
 		return -EINVAL;
 	}
@@ -3883,7 +3883,7 @@ static int btf_tag_resolve(struct btf_verifier_env *env,
 	    !env_type_is_resolved(env, next_type_id))
 		return env_stack_push(env, next_type, next_type_id);
 
-	component_idx = btf_type_tag(t)->component_idx;
+	component_idx = btf_type_decl_tag(t)->component_idx;
 	if (component_idx != -1) {
 		if (btf_type_is_var(next_type)) {
 			btf_verifier_log_type(env, v->t, "Invalid component_idx");
@@ -3909,18 +3909,18 @@ static int btf_tag_resolve(struct btf_verifier_env *env,
 	return 0;
 }
 
-static void btf_tag_log(struct btf_verifier_env *env, const struct btf_type *t)
+static void btf_decl_tag_log(struct btf_verifier_env *env, const struct btf_type *t)
 {
 	btf_verifier_log(env, "type=%u component_idx=%d", t->type,
-			 btf_type_tag(t)->component_idx);
+			 btf_type_decl_tag(t)->component_idx);
 }
 
-static const struct btf_kind_operations tag_ops = {
-	.check_meta = btf_tag_check_meta,
-	.resolve = btf_tag_resolve,
+static const struct btf_kind_operations decl_tag_ops = {
+	.check_meta = btf_decl_tag_check_meta,
+	.resolve = btf_decl_tag_resolve,
 	.check_member = btf_df_check_member,
 	.check_kflag_member = btf_df_check_kflag_member,
-	.log_details = btf_tag_log,
+	.log_details = btf_decl_tag_log,
 	.show = btf_df_show,
 };
 
@@ -4058,7 +4058,7 @@ static const struct btf_kind_operations * const kind_ops[NR_BTF_KINDS] = {
 	[BTF_KIND_VAR] = &var_ops,
 	[BTF_KIND_DATASEC] = &datasec_ops,
 	[BTF_KIND_FLOAT] = &float_ops,
-	[BTF_KIND_TAG] = &tag_ops,
+	[BTF_KIND_DECL_TAG] = &decl_tag_ops,
 };
 
 static s32 btf_check_meta(struct btf_verifier_env *env,
@@ -4143,7 +4143,7 @@ static bool btf_resolve_valid(struct btf_verifier_env *env,
 		return !btf_resolved_type_id(btf, type_id) &&
 		       !btf_resolved_type_size(btf, type_id);
 
-	if (btf_type_is_tag(t))
+	if (btf_type_is_decl_tag(t))
 		return btf_resolved_type_id(btf, type_id) &&
 		       !btf_resolved_type_size(btf, type_id);