Commit 3b1f89e7 authored by Kui-Feng Lee's avatar Kui-Feng Lee Committed by Martin KaFai Lau
Browse files

bpf: refactory struct_ops type initialization to a function. 



Move the majority of the code to bpf_struct_ops_init_one(), which can then
be utilized for the initialization of newly registered dynamically
allocated struct_ops types in the following patches.

Signed-off-by: default avatarKui-Feng Lee <thinker.li@gmail.com>
Link: https://lore.kernel.org/r/20240119225005.668602-2-thinker.li@gmail.com


Signed-off-by: default avatarMartin KaFai Lau <martin.lau@kernel.org>
parent b7d1af37

include/linux/btf.h

+1 −0
Original line number Diff line number Diff line
@@ -137,6 +137,7 @@ struct btf_struct_metas { 


extern const struct file_operations btf_fops;



const char *btf_get_name(const struct btf *btf);

void btf_get(struct btf *btf);

void btf_put(struct btf *btf);

int btf_new_fd(const union bpf_attr *attr, bpfptr_t uattr, u32 uattr_sz);

kernel/bpf/bpf_struct_ops.c

+83 −74
Original line number Diff line number Diff line
@@ -110,62 +110,48 @@ const struct bpf_prog_ops bpf_struct_ops_prog_ops = { 


static const struct btf_type *module_type;



void bpf_struct_ops_init(struct btf *btf, struct bpf_verifier_log *log)

static void bpf_struct_ops_init_one(struct bpf_struct_ops *st_ops,

				    struct btf *btf,

				    struct bpf_verifier_log *log)

{

	s32 type_id, value_id, module_id;

	const struct btf_member *member;

	struct bpf_struct_ops *st_ops;

	const struct btf_type *t;

	s32 type_id, value_id;

	char value_name[128];

	const char *mname;

	u32 i, j;



	/* Ensure BTF type is emitted for "struct bpf_struct_ops_##_name" */

#define BPF_STRUCT_OPS_TYPE(_name) BTF_TYPE_EMIT(struct bpf_struct_ops_##_name);

#include "bpf_struct_ops_types.h"

#undef BPF_STRUCT_OPS_TYPE



	module_id = btf_find_by_name_kind(btf, "module", BTF_KIND_STRUCT);

	if (module_id < 0) {

		pr_warn("Cannot find struct module in btf_vmlinux\n");

		return;

	}

	module_type = btf_type_by_id(btf, module_id);



	for (i = 0; i < ARRAY_SIZE(bpf_struct_ops); i++) {

		st_ops = bpf_struct_ops[i];

	int i;



	if (strlen(st_ops->name) + VALUE_PREFIX_LEN >=

	    sizeof(value_name)) {

		pr_warn("struct_ops name %s is too long\n",

			st_ops->name);

			continue;

		return;

	}

	sprintf(value_name, "%s%s", VALUE_PREFIX, st_ops->name);



	value_id = btf_find_by_name_kind(btf, value_name,

					 BTF_KIND_STRUCT);

	if (value_id < 0) {

			pr_warn("Cannot find struct %s in btf_vmlinux\n",

				value_name);

			continue;

		pr_warn("Cannot find struct %s in %s\n",

			value_name, btf_get_name(btf));

		return;

	}



	type_id = btf_find_by_name_kind(btf, st_ops->name,

					BTF_KIND_STRUCT);

	if (type_id < 0) {

			pr_warn("Cannot find struct %s in btf_vmlinux\n",

				st_ops->name);

			continue;

		pr_warn("Cannot find struct %s in %s\n",

			st_ops->name, btf_get_name(btf));

		return;

	}

	t = btf_type_by_id(btf, type_id);

	if (btf_type_vlen(t) > BPF_STRUCT_OPS_MAX_NR_MEMBERS) {

		pr_warn("Cannot support #%u members in struct %s\n",

			btf_type_vlen(t), st_ops->name);

			continue;

		return;

	}



		for_each_member(j, t, member) {

	for_each_member(i, t, member) {

		const struct btf_type *func_proto;



		mname = btf_name_by_offset(btf, member->name_off);
@@ -187,14 +173,14 @@ void bpf_struct_ops_init(struct btf *btf, struct bpf_verifier_log *log) 
		if (func_proto &&

		    btf_distill_func_proto(log, btf,

					   func_proto, mname,

						   &st_ops->func_models[j])) {

					   &st_ops->func_models[i])) {

			pr_warn("Error in parsing func ptr %s in struct %s\n",

				mname, st_ops->name);

			break;

		}

	}



		if (j == btf_type_vlen(t)) {

	if (i == btf_type_vlen(t)) {

		if (st_ops->init(btf)) {

			pr_warn("Error in init bpf_struct_ops %s\n",

				st_ops->name);
@@ -207,6 +193,29 @@ void bpf_struct_ops_init(struct btf *btf, struct bpf_verifier_log *log) 
		}

	}

}



void bpf_struct_ops_init(struct btf *btf, struct bpf_verifier_log *log)

{

	struct bpf_struct_ops *st_ops;

	s32 module_id;

	u32 i;



	/* Ensure BTF type is emitted for "struct bpf_struct_ops_##_name" */

#define BPF_STRUCT_OPS_TYPE(_name) BTF_TYPE_EMIT(struct bpf_struct_ops_##_name);

#include "bpf_struct_ops_types.h"

#undef BPF_STRUCT_OPS_TYPE



	module_id = btf_find_by_name_kind(btf, "module", BTF_KIND_STRUCT);

	if (module_id < 0) {

		pr_warn("Cannot find struct module in %s\n", btf_get_name(btf));

		return;

	}

	module_type = btf_type_by_id(btf, module_id);



	for (i = 0; i < ARRAY_SIZE(bpf_struct_ops); i++) {

		st_ops = bpf_struct_ops[i];

		bpf_struct_ops_init_one(st_ops, btf, log);

	}

}



extern struct btf *btf_vmlinux;

kernel/bpf/btf.c

+5 −0
Original line number Diff line number Diff line
@@ -1707,6 +1707,11 @@ static void btf_free_rcu(struct rcu_head *rcu) 
	btf_free(btf);

}



const char *btf_get_name(const struct btf *btf)

{

	return btf->name;

}



void btf_get(struct btf *btf)

{

	refcount_inc(&btf->refcnt);