Commit 689423db authored by Kui-Feng Lee's avatar Kui-Feng Lee Committed by Martin KaFai Lau
Browse files

bpf: lookup struct_ops types from a given module BTF. 



This is a preparation for searching for struct_ops types from a specified
module. BTF is always btf_vmlinux now. This patch passes a pointer of BTF
to bpf_struct_ops_find_value() and bpf_struct_ops_find(). Once the new
registration API of struct_ops types is used, other BTFs besides
btf_vmlinux can also be passed to them.

Signed-off-by: default avatarKui-Feng Lee <thinker.li@gmail.com>
Link: https://lore.kernel.org/r/20240119225005.668602-8-thinker.li@gmail.com


Signed-off-by: default avatarMartin KaFai Lau <martin.lau@kernel.org>
parent 1338b933

include/linux/bpf.h

+2 −2
Original line number Diff line number Diff line
@@ -1689,7 +1689,7 @@ struct bpf_struct_ops_desc { 


#if defined(CONFIG_BPF_JIT) && defined(CONFIG_BPF_SYSCALL)

#define BPF_MODULE_OWNER ((void *)((0xeB9FUL << 2) + POISON_POINTER_DELTA))

const struct bpf_struct_ops_desc *bpf_struct_ops_find(u32 type_id);

const struct bpf_struct_ops_desc *bpf_struct_ops_find(struct btf *btf, u32 type_id);

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

bool bpf_struct_ops_get(const void *kdata);

void bpf_struct_ops_put(const void *kdata);
@@ -1734,7 +1734,7 @@ int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr, 
#endif

void bpf_map_struct_ops_info_fill(struct bpf_map_info *info, struct bpf_map *map);

#else

static inline const struct bpf_struct_ops_desc *bpf_struct_ops_find(u32 type_id)

static inline const struct bpf_struct_ops_desc *bpf_struct_ops_find(struct btf *btf, u32 type_id)

{

	return NULL;

}

kernel/bpf/bpf_struct_ops.c

+6 −5
Original line number Diff line number Diff line
@@ -221,11 +221,11 @@ void bpf_struct_ops_init(struct btf *btf, struct bpf_verifier_log *log) 
extern struct btf *btf_vmlinux;



static const struct bpf_struct_ops_desc *

bpf_struct_ops_find_value(u32 value_id)

bpf_struct_ops_find_value(struct btf *btf, u32 value_id)

{

	unsigned int i;



	if (!value_id || !btf_vmlinux)

	if (!value_id || !btf)

		return NULL;



	for (i = 0; i < ARRAY_SIZE(bpf_struct_ops); i++) {
@@ -236,11 +236,12 @@ bpf_struct_ops_find_value(u32 value_id) 
	return NULL;

}



const struct bpf_struct_ops_desc *bpf_struct_ops_find(u32 type_id)

const struct bpf_struct_ops_desc *

bpf_struct_ops_find(struct btf *btf, u32 type_id)

{

	unsigned int i;



	if (!type_id || !btf_vmlinux)

	if (!type_id || !btf)

		return NULL;



	for (i = 0; i < ARRAY_SIZE(bpf_struct_ops); i++) {
@@ -682,7 +683,7 @@ static struct bpf_map *bpf_struct_ops_map_alloc(union bpf_attr *attr) 
	struct bpf_map *map;

	int ret;



	st_ops_desc = bpf_struct_ops_find_value(attr->btf_vmlinux_value_type_id);

	st_ops_desc = bpf_struct_ops_find_value(btf_vmlinux, attr->btf_vmlinux_value_type_id);

	if (!st_ops_desc)

		return ERR_PTR(-ENOTSUPP);

kernel/bpf/verifier.c

+1 −1
Original line number Diff line number Diff line
@@ -20298,7 +20298,7 @@ static int check_struct_ops_btf_id(struct bpf_verifier_env *env) 
	}









	btf_id = prog->aux->attach_btf_id;









	st_ops_desc = bpf_struct_ops_find(btf_id);









	st_ops_desc = bpf_struct_ops_find(btf_vmlinux, btf_id);









	if (!st_ops_desc) {









		verbose(env, "attach_btf_id %u is not a supported struct\n",









			btf_id);