[linux-block.git] / include / linux / btf.h

/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright (c) 2018 Facebook */

#ifndef _LINUX_BTF_H
#define _LINUX_BTF_H 1

#include <linux/types.h>
#include <linux/bpfptr.h>
#include <linux/bsearch.h>
#include <linux/btf_ids.h>
#include <uapi/linux/btf.h>
#include <uapi/linux/bpf.h>

#define BTF_TYPE_EMIT(type) ((void)(type *)0)
#define BTF_TYPE_EMIT_ENUM(enum_val) ((void)enum_val)

/* These need to be macros, as the expressions are used in assembler input */
#define KF_ACQUIRE	(1 << 0) /* kfunc is an acquire function */
#define KF_RELEASE	(1 << 1) /* kfunc is a release function */
#define KF_RET_NULL	(1 << 2) /* kfunc returns a pointer that may be NULL */
/* Trusted arguments are those which are guaranteed to be valid when passed to
 * the kfunc. It is used to enforce that pointers obtained from either acquire
 * kfuncs, or from the main kernel on a tracepoint or struct_ops callback
 * invocation, remain unmodified when being passed to helpers taking trusted
 * args.
 *
 * Consider, for example, the following new task tracepoint:
 *
 *	SEC("tp_btf/task_newtask")
 *	int BPF_PROG(new_task_tp, struct task_struct *task, u64 clone_flags)
 *	{
 *		...
 *	}
 *
 * And the following kfunc:
 *
 *	BTF_ID_FLAGS(func, bpf_task_acquire, KF_ACQUIRE | KF_TRUSTED_ARGS)
 *
 * All invocations to the kfunc must pass the unmodified, unwalked task:
 *
 *	bpf_task_acquire(task);		    // Allowed
 *	bpf_task_acquire(task->last_wakee); // Rejected, walked task
 *
 * Programs may also pass referenced tasks directly to the kfunc:
 *
 *	struct task_struct *acquired;
 *
 *	acquired = bpf_task_acquire(task);	// Allowed, same as above
 *	bpf_task_acquire(acquired);		// Allowed
 *	bpf_task_acquire(task);			// Allowed
 *	bpf_task_acquire(acquired->last_wakee); // Rejected, walked task
 *
 * Programs may _not_, however, pass a task from an arbitrary fentry/fexit, or
 * kprobe/kretprobe to the kfunc, as BPF cannot guarantee that all of these
 * pointers are guaranteed to be safe. For example, the following BPF program
 * would be rejected:
 *
 * SEC("kretprobe/free_task")
 * int BPF_PROG(free_task_probe, struct task_struct *tsk)
 * {
 *	struct task_struct *acquired;
 *
 *	acquired = bpf_task_acquire(acquired); // Rejected, not a trusted pointer
 *	bpf_task_release(acquired);
 *
 *	return 0;
 * }
 */
#define KF_TRUSTED_ARGS (1 << 4) /* kfunc only takes trusted pointer arguments */
#define KF_SLEEPABLE    (1 << 5) /* kfunc may sleep */
#define KF_DESTRUCTIVE  (1 << 6) /* kfunc performs destructive actions */
#define KF_RCU          (1 << 7) /* kfunc takes either rcu or trusted pointer arguments */
/* only one of KF_ITER_{NEW,NEXT,DESTROY} could be specified per kfunc */
#define KF_ITER_NEW     (1 << 8) /* kfunc implements BPF iter constructor */
#define KF_ITER_NEXT    (1 << 9) /* kfunc implements BPF iter next method */
#define KF_ITER_DESTROY (1 << 10) /* kfunc implements BPF iter destructor */

/*
 * Tag marking a kernel function as a kfunc. This is meant to minimize the
 * amount of copy-paste that kfunc authors have to include for correctness so
 * as to avoid issues such as the compiler inlining or eliding either a static
 * kfunc, or a global kfunc in an LTO build.
 */
#define __bpf_kfunc __used noinline

/*
 * Return the name of the passed struct, if exists, or halt the build if for
 * example the structure gets renamed. In this way, developers have to revisit
 * the code using that structure name, and update it accordingly.
 */
#define stringify_struct(x)			\
	({ BUILD_BUG_ON(sizeof(struct x) < 0);	\
	   __stringify(x); })

struct btf;
struct btf_member;
struct btf_type;
union bpf_attr;
struct btf_show;
struct btf_id_set;

struct btf_kfunc_id_set {
	struct module *owner;
	struct btf_id_set8 *set;
};

struct btf_id_dtor_kfunc {
	u32 btf_id;
	u32 kfunc_btf_id;
};

struct btf_struct_meta {
	u32 btf_id;
	struct btf_record *record;
};

struct btf_struct_metas {
	u32 cnt;
	struct btf_struct_meta types[];
};

extern const struct file_operations btf_fops;

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);
struct btf *btf_get_by_fd(int fd);
int btf_get_info_by_fd(const struct btf *btf,
		       const union bpf_attr *attr,
		       union bpf_attr __user *uattr);
/* Figure out the size of a type_id.  If type_id is a modifier
 * (e.g. const), it will be resolved to find out the type with size.
 *
 * For example:
 * In describing "const void *",  type_id is "const" and "const"
 * refers to "void *".  The return type will be "void *".
 *
 * If type_id is a simple "int", then return type will be "int".
 *
 * @btf: struct btf object
 * @type_id: Find out the size of type_id. The type_id of the return
 *           type is set to *type_id.
 * @ret_size: It can be NULL.  If not NULL, the size of the return
 *            type is set to *ret_size.
 * Return: The btf_type (resolved to another type with size info if needed).
 *         NULL is returned if type_id itself does not have size info
 *         (e.g. void) or it cannot be resolved to another type that
 *         has size info.
 *         *type_id and *ret_size will not be changed in the
 *         NULL return case.
 */
const struct btf_type *btf_type_id_size(const struct btf *btf,
					u32 *type_id,
					u32 *ret_size);

/*
 * Options to control show behaviour.
 *	- BTF_SHOW_COMPACT: no formatting around type information
 *	- BTF_SHOW_NONAME: no struct/union member names/types
 *	- BTF_SHOW_PTR_RAW: show raw (unobfuscated) pointer values;
 *	  equivalent to %px.
 *	- BTF_SHOW_ZERO: show zero-valued struct/union members; they
 *	  are not displayed by default
 *	- BTF_SHOW_UNSAFE: skip use of bpf_probe_read() to safely read
 *	  data before displaying it.
 */
#define BTF_SHOW_COMPACT	BTF_F_COMPACT
#define BTF_SHOW_NONAME		BTF_F_NONAME
#define BTF_SHOW_PTR_RAW	BTF_F_PTR_RAW
#define BTF_SHOW_ZERO		BTF_F_ZERO
#define BTF_SHOW_UNSAFE		(1ULL << 4)

void btf_type_seq_show(const struct btf *btf, u32 type_id, void *obj,
		       struct seq_file *m);
int btf_type_seq_show_flags(const struct btf *btf, u32 type_id, void *obj,
			    struct seq_file *m, u64 flags);

/*
 * Copy len bytes of string representation of obj of BTF type_id into buf.
 *
 * @btf: struct btf object
 * @type_id: type id of type obj points to
 * @obj: pointer to typed data
 * @buf: buffer to write to
 * @len: maximum length to write to buf
 * @flags: show options (see above)
 *
 * Return: length that would have been/was copied as per snprintf, or
 *	   negative error.
 */
int btf_type_snprintf_show(const struct btf *btf, u32 type_id, void *obj,
			   char *buf, int len, u64 flags);

int btf_get_fd_by_id(u32 id);
u32 btf_obj_id(const struct btf *btf);
bool btf_is_kernel(const struct btf *btf);
bool btf_is_module(const struct btf *btf);
struct module *btf_try_get_module(const struct btf *btf);
u32 btf_nr_types(const struct btf *btf);
bool btf_member_is_reg_int(const struct btf *btf, const struct btf_type *s,
			   const struct btf_member *m,
			   u32 expected_offset, u32 expected_size);
int btf_find_spin_lock(const struct btf *btf, const struct btf_type *t);
int btf_find_timer(const struct btf *btf, const struct btf_type *t);
struct btf_record *btf_parse_fields(const struct btf *btf, const struct btf_type *t,
				    u32 field_mask, u32 value_size);
int btf_check_and_fixup_fields(const struct btf *btf, struct btf_record *rec);
bool btf_type_is_void(const struct btf_type *t);
s32 btf_find_by_name_kind(const struct btf *btf, const char *name, u8 kind);
const struct btf_type *btf_type_skip_modifiers(const struct btf *btf,
					       u32 id, u32 *res_id);
const struct btf_type *btf_type_resolve_ptr(const struct btf *btf,
					    u32 id, u32 *res_id);
const struct btf_type *btf_type_resolve_func_ptr(const struct btf *btf,
						 u32 id, u32 *res_id);
const struct btf_type *
btf_resolve_size(const struct btf *btf, const struct btf_type *type,
		 u32 *type_size);
const char *btf_type_str(const struct btf_type *t);

#define for_each_member(i, struct_type, member)			\
	for (i = 0, member = btf_type_member(struct_type);	\
	     i < btf_type_vlen(struct_type);			\
	     i++, member++)

#define for_each_vsi(i, datasec_type, member)			\
	for (i = 0, member = btf_type_var_secinfo(datasec_type);	\
	     i < btf_type_vlen(datasec_type);			\
	     i++, member++)

static inline bool btf_type_is_ptr(const struct btf_type *t)
{
	return BTF_INFO_KIND(t->info) == BTF_KIND_PTR;
}

static inline bool btf_type_is_int(const struct btf_type *t)
{
	return BTF_INFO_KIND(t->info) == BTF_KIND_INT;
}

static inline bool btf_type_is_small_int(const struct btf_type *t)
{
	return btf_type_is_int(t) && t->size <= sizeof(u64);
}

static inline u8 btf_int_encoding(const struct btf_type *t)
{
	return BTF_INT_ENCODING(*(u32 *)(t + 1));
}

static inline bool btf_type_is_signed_int(const struct btf_type *t)
{
	return btf_type_is_int(t) && (btf_int_encoding(t) & BTF_INT_SIGNED);
}

static inline bool btf_type_is_enum(const struct btf_type *t)
{
	return BTF_INFO_KIND(t->info) == BTF_KIND_ENUM;
}

static inline bool btf_is_any_enum(const struct btf_type *t)
{
	return BTF_INFO_KIND(t->info) == BTF_KIND_ENUM ||
	       BTF_INFO_KIND(t->info) == BTF_KIND_ENUM64;
}

static inline bool btf_kind_core_compat(const struct btf_type *t1,
					const struct btf_type *t2)
{
	return BTF_INFO_KIND(t1->info) == BTF_INFO_KIND(t2->info) ||
	       (btf_is_any_enum(t1) && btf_is_any_enum(t2));
}

static inline bool str_is_empty(const char *s)
{
	return !s || !s[0];
}

static inline u16 btf_kind(const struct btf_type *t)
{
	return BTF_INFO_KIND(t->info);
}

static inline bool btf_is_enum(const struct btf_type *t)
{
	return btf_kind(t) == BTF_KIND_ENUM;
}

static inline bool btf_is_enum64(const struct btf_type *t)
{
	return btf_kind(t) == BTF_KIND_ENUM64;
}

static inline u64 btf_enum64_value(const struct btf_enum64 *e)
{
	return ((u64)e->val_hi32 << 32) | e->val_lo32;
}

static inline bool btf_is_composite(const struct btf_type *t)
{
	u16 kind = btf_kind(t);

	return kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION;
}

static inline bool btf_is_array(const struct btf_type *t)
{
	return btf_kind(t) == BTF_KIND_ARRAY;
}

static inline bool btf_is_int(const struct btf_type *t)
{
	return btf_kind(t) == BTF_KIND_INT;
}

static inline bool btf_is_ptr(const struct btf_type *t)
{
	return btf_kind(t) == BTF_KIND_PTR;
}

static inline u8 btf_int_offset(const struct btf_type *t)
{
	return BTF_INT_OFFSET(*(u32 *)(t + 1));
}

static inline bool btf_type_is_scalar(const struct btf_type *t)
{
	return btf_type_is_int(t) || btf_type_is_enum(t);
}

static inline bool btf_type_is_typedef(const struct btf_type *t)
{
	return BTF_INFO_KIND(t->info) == BTF_KIND_TYPEDEF;
}

static inline bool btf_type_is_volatile(const struct btf_type *t)
{
	return BTF_INFO_KIND(t->info) == BTF_KIND_VOLATILE;
}

static inline bool btf_type_is_func(const struct btf_type *t)
{
	return BTF_INFO_KIND(t->info) == BTF_KIND_FUNC;
}

static inline bool btf_type_is_func_proto(const struct btf_type *t)
{
	return BTF_INFO_KIND(t->info) == BTF_KIND_FUNC_PROTO;
}

static inline bool btf_type_is_var(const struct btf_type *t)
{
	return BTF_INFO_KIND(t->info) == BTF_KIND_VAR;
}

static inline bool btf_type_is_type_tag(const struct btf_type *t)
{
	return BTF_INFO_KIND(t->info) == BTF_KIND_TYPE_TAG;
}

/* union is only a special case of struct:
 * all its offsetof(member) == 0
 */
static inline bool btf_type_is_struct(const struct btf_type *t)
{
	u8 kind = BTF_INFO_KIND(t->info);

	return kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION;
}

static inline bool __btf_type_is_struct(const struct btf_type *t)
{
	return BTF_INFO_KIND(t->info) == BTF_KIND_STRUCT;
}

static inline bool btf_type_is_array(const struct btf_type *t)
{
	return BTF_INFO_KIND(t->info) == BTF_KIND_ARRAY;
}

static inline u16 btf_type_vlen(const struct btf_type *t)
{
	return BTF_INFO_VLEN(t->info);
}

static inline u16 btf_vlen(const struct btf_type *t)
{
	return btf_type_vlen(t);
}

static inline u16 btf_func_linkage(const struct btf_type *t)
{
	return BTF_INFO_VLEN(t->info);
}

static inline bool btf_type_kflag(const struct btf_type *t)
{
	return BTF_INFO_KFLAG(t->info);
}

static inline u32 __btf_member_bit_offset(const struct btf_type *struct_type,
					  const struct btf_member *member)
{
	return btf_type_kflag(struct_type) ? BTF_MEMBER_BIT_OFFSET(member->offset)
					   : member->offset;
}

static inline u32 __btf_member_bitfield_size(const struct btf_type *struct_type,
					     const struct btf_member *member)
{
	return btf_type_kflag(struct_type) ? BTF_MEMBER_BITFIELD_SIZE(member->offset)
					   : 0;
}

static inline struct btf_member *btf_members(const struct btf_type *t)
{
	return (struct btf_member *)(t + 1);
}

static inline u32 btf_member_bit_offset(const struct btf_type *t, u32 member_idx)
{
	const struct btf_member *m = btf_members(t) + member_idx;

	return __btf_member_bit_offset(t, m);
}

static inline u32 btf_member_bitfield_size(const struct btf_type *t, u32 member_idx)
{
	const struct btf_member *m = btf_members(t) + member_idx;

	return __btf_member_bitfield_size(t, m);
}

static inline const struct btf_member *btf_type_member(const struct btf_type *t)
{
	return (const struct btf_member *)(t + 1);
}

static inline struct btf_array *btf_array(const struct btf_type *t)
{
	return (struct btf_array *)(t + 1);
}

static inline struct btf_enum *btf_enum(const struct btf_type *t)
{
	return (struct btf_enum *)(t + 1);
}

static inline struct btf_enum64 *btf_enum64(const struct btf_type *t)
{
	return (struct btf_enum64 *)(t + 1);
}

static inline const struct btf_var_secinfo *btf_type_var_secinfo(
		const struct btf_type *t)
{
	return (const struct btf_var_secinfo *)(t + 1);
}

static inline struct btf_param *btf_params(const struct btf_type *t)
{
	return (struct btf_param *)(t + 1);
}

static inline int btf_id_cmp_func(const void *a, const void *b)
{
	const int *pa = a, *pb = b;

	return *pa - *pb;
}

static inline bool btf_id_set_contains(const struct btf_id_set *set, u32 id)
{
	return bsearch(&id, set->ids, set->cnt, sizeof(u32), btf_id_cmp_func) != NULL;
}

static inline void *btf_id_set8_contains(const struct btf_id_set8 *set, u32 id)
{
	return bsearch(&id, set->pairs, set->cnt, sizeof(set->pairs[0]), btf_id_cmp_func);
}

struct bpf_prog;
struct bpf_verifier_log;

#ifdef CONFIG_BPF_SYSCALL
const struct btf_type *btf_type_by_id(const struct btf *btf, u32 type_id);
const char *btf_name_by_offset(const struct btf *btf, u32 offset);
struct btf *btf_parse_vmlinux(void);
struct btf *bpf_prog_get_target_btf(const struct bpf_prog *prog);
u32 *btf_kfunc_id_set_contains(const struct btf *btf,
			       enum bpf_prog_type prog_type,
			       u32 kfunc_btf_id);
u32 *btf_kfunc_is_modify_return(const struct btf *btf, u32 kfunc_btf_id);
int register_btf_kfunc_id_set(enum bpf_prog_type prog_type,
			      const struct btf_kfunc_id_set *s);
int register_btf_fmodret_id_set(const struct btf_kfunc_id_set *kset);
s32 btf_find_dtor_kfunc(struct btf *btf, u32 btf_id);
int register_btf_id_dtor_kfuncs(const struct btf_id_dtor_kfunc *dtors, u32 add_cnt,
				struct module *owner);
struct btf_struct_meta *btf_find_struct_meta(const struct btf *btf, u32 btf_id);
const struct btf_member *
btf_get_prog_ctx_type(struct bpf_verifier_log *log, const struct btf *btf,
		      const struct btf_type *t, enum bpf_prog_type prog_type,
		      int arg);
int get_kern_ctx_btf_id(struct bpf_verifier_log *log, enum bpf_prog_type prog_type);
bool btf_types_are_same(const struct btf *btf1, u32 id1,
			const struct btf *btf2, u32 id2);
#else
static inline const struct btf_type *btf_type_by_id(const struct btf *btf,
						    u32 type_id)
{
	return NULL;
}
static inline const char *btf_name_by_offset(const struct btf *btf,
					     u32 offset)
{
	return NULL;
}
static inline u32 *btf_kfunc_id_set_contains(const struct btf *btf,
					     enum bpf_prog_type prog_type,
					     u32 kfunc_btf_id)
{
	return NULL;
}
static inline int register_btf_kfunc_id_set(enum bpf_prog_type prog_type,
					    const struct btf_kfunc_id_set *s)
{
	return 0;
}
static inline s32 btf_find_dtor_kfunc(struct btf *btf, u32 btf_id)
{
	return -ENOENT;
}
static inline int register_btf_id_dtor_kfuncs(const struct btf_id_dtor_kfunc *dtors,
					      u32 add_cnt, struct module *owner)
{
	return 0;
}
static inline struct btf_struct_meta *btf_find_struct_meta(const struct btf *btf, u32 btf_id)
{
	return NULL;
}
static inline const struct btf_member *
btf_get_prog_ctx_type(struct bpf_verifier_log *log, const struct btf *btf,
		      const struct btf_type *t, enum bpf_prog_type prog_type,
		      int arg)
{
	return NULL;
}
static inline int get_kern_ctx_btf_id(struct bpf_verifier_log *log,
				      enum bpf_prog_type prog_type) {
	return -EINVAL;
}
static inline bool btf_types_are_same(const struct btf *btf1, u32 id1,
				      const struct btf *btf2, u32 id2)
{
	return false;
}
#endif

static inline bool btf_type_is_struct_ptr(struct btf *btf, const struct btf_type *t)
{
	if (!btf_type_is_ptr(t))
		return false;

	t = btf_type_skip_modifiers(btf, t->type, NULL);

	return btf_type_is_struct(t);
}

#endif
Commit	Line	Data
eb3f595d MKL	1	/* SPDX-License-Identifier: GPL-2.0 */
	2	/* Copyright (c) 2018 Facebook */
	3
	4	#ifndef _LINUX_BTF_H
	5	#define _LINUX_BTF_H 1
	6
	7	#include <linux/types.h>
14f267d9	8	#include <linux/bpfptr.h>
8ffa5cc1 KKD	9	#include <linux/bsearch.h>
8ffa5cc1 KKD	10	#include <linux/btf_ids.h>
38207291	11	#include <uapi/linux/btf.h>
c4d0bfb4	12	#include <uapi/linux/bpf.h>
eb3f595d	13
85d33df3	14	#define BTF_TYPE_EMIT(type) ((void)(type *)0)
97a19caf	15	#define BTF_TYPE_EMIT_ENUM(enum_val) ((void)enum_val)
85d33df3	16
a4703e31 KKD	17	/* These need to be macros, as the expressions are used in assembler input */
	18	#define KF_ACQUIRE (1 << 0) /* kfunc is an acquire function */
	19	#define KF_RELEASE (1 << 1) /* kfunc is a release function */
	20	#define KF_RET_NULL (1 << 2) /* kfunc returns a pointer that may be NULL */
3f00c523 DV	21	/* Trusted arguments are those which are guaranteed to be valid when passed to
	22	* the kfunc. It is used to enforce that pointers obtained from either acquire
	23	* kfuncs, or from the main kernel on a tracepoint or struct_ops callback
	24	* invocation, remain unmodified when being passed to helpers taking trusted
	25	* args.
	26	*
	27	* Consider, for example, the following new task tracepoint:
	28	*
	29	* SEC("tp_btf/task_newtask")
	30	* int BPF_PROG(new_task_tp, struct task_struct *task, u64 clone_flags)
	31	* {
	32	* ...
	33	* }
	34	*
	35	* And the following kfunc:
	36	*
	37	* BTF_ID_FLAGS(func, bpf_task_acquire, KF_ACQUIRE \| KF_TRUSTED_ARGS)
	38	*
	39	* All invocations to the kfunc must pass the unmodified, unwalked task:
	40	*
	41	* bpf_task_acquire(task); // Allowed
	42	* bpf_task_acquire(task->last_wakee); // Rejected, walked task
	43	*
	44	* Programs may also pass referenced tasks directly to the kfunc:
	45	*
	46	* struct task_struct *acquired;
	47	*
	48	* acquired = bpf_task_acquire(task); // Allowed, same as above
	49	* bpf_task_acquire(acquired); // Allowed
	50	* bpf_task_acquire(task); // Allowed
	51	* bpf_task_acquire(acquired->last_wakee); // Rejected, walked task
	52	*
	53	* Programs may _not_, however, pass a task from an arbitrary fentry/fexit, or
	54	* kprobe/kretprobe to the kfunc, as BPF cannot guarantee that all of these
	55	* pointers are guaranteed to be safe. For example, the following BPF program
	56	* would be rejected:
	57	*
	58	* SEC("kretprobe/free_task")
	59	* int BPF_PROG(free_task_probe, struct task_struct *tsk)
	60	* {
	61	* struct task_struct *acquired;
	62	*
	63	* acquired = bpf_task_acquire(acquired); // Rejected, not a trusted pointer
	64	* bpf_task_release(acquired);
	65	*
	66	* return 0;
	67	* }
56e948ff KKD	68	*/
56e948ff KKD	69	#define KF_TRUSTED_ARGS (1 << 4) /* kfunc only takes trusted pointer arguments */
4dd48c6f AS	70	#define KF_SLEEPABLE (1 << 5) /* kfunc may sleep */
4dd48c6f AS	71	#define KF_DESTRUCTIVE (1 << 6) /* kfunc performs destructive actions */
20c09d92	72	#define KF_RCU (1 << 7) /* kfunc takes either rcu or trusted pointer arguments */
215bf496 AN	73	/* only one of KF_ITER_{NEW,NEXT,DESTROY} could be specified per kfunc */
	74	#define KF_ITER_NEW (1 << 8) /* kfunc implements BPF iter constructor */
	75	#define KF_ITER_NEXT (1 << 9) /* kfunc implements BPF iter next method */
	76	#define KF_ITER_DESTROY (1 << 10) /* kfunc implements BPF iter destructor */
dee872e1	77
57e7c169 DV	78	/*
	79	* Tag marking a kernel function as a kfunc. This is meant to minimize the
	80	* amount of copy-paste that kfunc authors have to include for correctness so
	81	* as to avoid issues such as the compiler inlining or eliding either a static
	82	* kfunc, or a global kfunc in an LTO build.
	83	*/
	84	#define __bpf_kfunc __used noinline
	85
b8d31762 RS	86	/*
	87	* Return the name of the passed struct, if exists, or halt the build if for
	88	* example the structure gets renamed. In this way, developers have to revisit
	89	* the code using that structure name, and update it accordingly.
	90	*/
	91	#define stringify_struct(x) \
	92	({ BUILD_BUG_ON(sizeof(struct x) < 0); \
	93	__stringify(x); })
	94
eb3f595d	95	struct btf;
ffa0c1cf	96	struct btf_member;
eb3f595d	97	struct btf_type;
f56a653c	98	union bpf_attr;
31d0bc81	99	struct btf_show;
dee872e1 KKD	100	struct btf_id_set;
	101
	102	struct btf_kfunc_id_set {
	103	struct module *owner;
a4703e31	104	struct btf_id_set8 *set;
dee872e1	105	};
eb3f595d	106
5ce937d6 KKD	107	struct btf_id_dtor_kfunc {
	108	u32 btf_id;
	109	u32 kfunc_btf_id;
	110	};
	111
8ffa5cc1 KKD	112	struct btf_struct_meta {
	113	u32 btf_id;
	114	struct btf_record *record;
8ffa5cc1 KKD	115	};
	116
	117	struct btf_struct_metas {
	118	u32 cnt;
	119	struct btf_struct_meta types[];
	120	};
	121
60197cfb MKL	122	extern const struct file_operations btf_fops;
60197cfb MKL	123
22dc4a0f	124	void btf_get(struct btf *btf);
f56a653c	125	void btf_put(struct btf *btf);
47a71c1f	126	int btf_new_fd(const union bpf_attr *attr, bpfptr_t uattr, u32 uattr_sz);
f56a653c	127	struct btf *btf_get_by_fd(int fd);
60197cfb MKL	128	int btf_get_info_by_fd(const struct btf *btf,
	129	const union bpf_attr *attr,
	130	union bpf_attr __user *uattr);
eb3f595d MKL	131	/* Figure out the size of a type_id. If type_id is a modifier
	132	* (e.g. const), it will be resolved to find out the type with size.
	133	*
	134	* For example:
	135	* In describing "const void *", type_id is "const" and "const"
	136	* refers to "void ". The return type will be "void ".
	137	*
	138	* If type_id is a simple "int", then return type will be "int".
	139	*
	140	* @btf: struct btf object
	141	* @type_id: Find out the size of type_id. The type_id of the return
	142	* type is set to *type_id.
	143	* @ret_size: It can be NULL. If not NULL, the size of the return
	144	* type is set to *ret_size.
	145	* Return: The btf_type (resolved to another type with size info if needed).
	146	* NULL is returned if type_id itself does not have size info
	147	* (e.g. void) or it cannot be resolved to another type that
	148	* has size info.
	149	* type_id and ret_size will not be changed in the
	150	* NULL return case.
	151	*/
	152	const struct btf_type btf_type_id_size(const struct btf btf,
	153	u32 *type_id,
	154	u32 *ret_size);
31d0bc81 AM	155
	156	/*
	157	* Options to control show behaviour.
	158	* - BTF_SHOW_COMPACT: no formatting around type information
	159	* - BTF_SHOW_NONAME: no struct/union member names/types
	160	* - BTF_SHOW_PTR_RAW: show raw (unobfuscated) pointer values;
	161	* equivalent to %px.
	162	* - BTF_SHOW_ZERO: show zero-valued struct/union members; they
	163	* are not displayed by default
	164	* - BTF_SHOW_UNSAFE: skip use of bpf_probe_read() to safely read
	165	* data before displaying it.
	166	*/
c4d0bfb4 AM	167	#define BTF_SHOW_COMPACT BTF_F_COMPACT
	168	#define BTF_SHOW_NONAME BTF_F_NONAME
	169	#define BTF_SHOW_PTR_RAW BTF_F_PTR_RAW
	170	#define BTF_SHOW_ZERO BTF_F_ZERO
31d0bc81 AM	171	#define BTF_SHOW_UNSAFE (1ULL << 4)
31d0bc81 AM	172
b00b8dae MKL	173	void btf_type_seq_show(const struct btf btf, u32 type_id, void obj,
b00b8dae MKL	174	struct seq_file *m);
eb411377 AM	175	int btf_type_seq_show_flags(const struct btf btf, u32 type_id, void obj,
eb411377 AM	176	struct seq_file *m, u64 flags);
31d0bc81 AM	177
	178	/*
	179	* Copy len bytes of string representation of obj of BTF type_id into buf.
	180	*
	181	* @btf: struct btf object
	182	* @type_id: type id of type obj points to
	183	* @obj: pointer to typed data
	184	* @buf: buffer to write to
	185	* @len: maximum length to write to buf
	186	* @flags: show options (see above)
	187	*
	188	* Return: length that would have been/was copied as per snprintf, or
	189	* negative error.
	190	*/
	191	int btf_type_snprintf_show(const struct btf btf, u32 type_id, void obj,
	192	char *buf, int len, u64 flags);
	193
78958fca	194	int btf_get_fd_by_id(u32 id);
22dc4a0f	195	u32 btf_obj_id(const struct btf *btf);
290248a5	196	bool btf_is_kernel(const struct btf *btf);
541c3bad AN	197	bool btf_is_module(const struct btf *btf);
	198	struct module btf_try_get_module(const struct btf btf);
	199	u32 btf_nr_types(const struct btf *btf);
ffa0c1cf YS	200	bool btf_member_is_reg_int(const struct btf btf, const struct btf_type s,
	201	const struct btf_member *m,
	202	u32 expected_offset, u32 expected_size);
d83525ca	203	int btf_find_spin_lock(const struct btf btf, const struct btf_type t);
68134668	204	int btf_find_timer(const struct btf btf, const struct btf_type t);
db559117 KKD	205	struct btf_record btf_parse_fields(const struct btf btf, const struct btf_type *t,
db559117 KKD	206	u32 field_mask, u32 value_size);
865ce09a	207	int btf_check_and_fixup_fields(const struct btf btf, struct btf_record rec);
2824ecb7	208	bool btf_type_is_void(const struct btf_type *t);
27ae7997 MKL	209	s32 btf_find_by_name_kind(const struct btf btf, const char name, u8 kind);
	210	const struct btf_type btf_type_skip_modifiers(const struct btf btf,
	211	u32 id, u32 *res_id);
	212	const struct btf_type btf_type_resolve_ptr(const struct btf btf,
	213	u32 id, u32 *res_id);
	214	const struct btf_type btf_type_resolve_func_ptr(const struct btf btf,
	215	u32 id, u32 *res_id);
85d33df3 MKL	216	const struct btf_type *
85d33df3 MKL	217	btf_resolve_size(const struct btf btf, const struct btf_type type,
6298399b	218	u32 *type_size);
e6ac2450	219	const char btf_type_str(const struct btf_type t);
27ae7997 MKL	220
	221	#define for_each_member(i, struct_type, member) \
	222	for (i = 0, member = btf_type_member(struct_type); \
	223	i < btf_type_vlen(struct_type); \
	224	i++, member++)
f6161a8f	225
eaa6bcb7 HL	226	#define for_each_vsi(i, datasec_type, member) \
	227	for (i = 0, member = btf_type_var_secinfo(datasec_type); \
	228	i < btf_type_vlen(datasec_type); \
	229	i++, member++)
	230
38207291 MKL	231	static inline bool btf_type_is_ptr(const struct btf_type *t)
	232	{
	233	return BTF_INFO_KIND(t->info) == BTF_KIND_PTR;
	234	}
	235
	236	static inline bool btf_type_is_int(const struct btf_type *t)
	237	{
	238	return BTF_INFO_KIND(t->info) == BTF_KIND_INT;
	239	}
	240
a9b59159 JF	241	static inline bool btf_type_is_small_int(const struct btf_type *t)
	242	{
	243	return btf_type_is_int(t) && t->size <= sizeof(u64);
	244	}
	245
49f67f39 IL	246	static inline u8 btf_int_encoding(const struct btf_type *t)
	247	{
	248	return BTF_INT_ENCODING((u32 )(t + 1));
	249	}
	250
	251	static inline bool btf_type_is_signed_int(const struct btf_type *t)
	252	{
	253	return btf_type_is_int(t) && (btf_int_encoding(t) & BTF_INT_SIGNED);
	254	}
	255
38207291 MKL	256	static inline bool btf_type_is_enum(const struct btf_type *t)
	257	{
	258	return BTF_INFO_KIND(t->info) == BTF_KIND_ENUM;
	259	}
	260
6089fb32 YS	261	static inline bool btf_is_any_enum(const struct btf_type *t)
	262	{
	263	return BTF_INFO_KIND(t->info) == BTF_KIND_ENUM \|\|
	264	BTF_INFO_KIND(t->info) == BTF_KIND_ENUM64;
	265	}
	266
	267	static inline bool btf_kind_core_compat(const struct btf_type *t1,
	268	const struct btf_type *t2)
	269	{
	270	return BTF_INFO_KIND(t1->info) == BTF_INFO_KIND(t2->info) \|\|
	271	(btf_is_any_enum(t1) && btf_is_any_enum(t2));
	272	}
	273
29db4bea AS	274	static inline bool str_is_empty(const char *s)
	275	{
	276	return !s \|\| !s[0];
	277	}
	278
	279	static inline u16 btf_kind(const struct btf_type *t)
	280	{
	281	return BTF_INFO_KIND(t->info);
	282	}
	283
	284	static inline bool btf_is_enum(const struct btf_type *t)
	285	{
	286	return btf_kind(t) == BTF_KIND_ENUM;
	287	}
	288
6089fb32 YS	289	static inline bool btf_is_enum64(const struct btf_type *t)
	290	{
	291	return btf_kind(t) == BTF_KIND_ENUM64;
	292	}
	293
	294	static inline u64 btf_enum64_value(const struct btf_enum64 *e)
	295	{
	296	return ((u64)e->val_hi32 << 32) \| e->val_lo32;
	297	}
	298
29db4bea AS	299	static inline bool btf_is_composite(const struct btf_type *t)
	300	{
	301	u16 kind = btf_kind(t);
	302
	303	return kind == BTF_KIND_STRUCT \|\| kind == BTF_KIND_UNION;
	304	}
	305
	306	static inline bool btf_is_array(const struct btf_type *t)
	307	{
	308	return btf_kind(t) == BTF_KIND_ARRAY;
	309	}
	310
	311	static inline bool btf_is_int(const struct btf_type *t)
	312	{
	313	return btf_kind(t) == BTF_KIND_INT;
	314	}
	315
	316	static inline bool btf_is_ptr(const struct btf_type *t)
	317	{
	318	return btf_kind(t) == BTF_KIND_PTR;
	319	}
	320
	321	static inline u8 btf_int_offset(const struct btf_type *t)
	322	{
	323	return BTF_INT_OFFSET((u32 )(t + 1));
	324	}
	325
34747c41 MKL	326	static inline bool btf_type_is_scalar(const struct btf_type *t)
	327	{
	328	return btf_type_is_int(t) \|\| btf_type_is_enum(t);
	329	}
	330
38207291 MKL	331	static inline bool btf_type_is_typedef(const struct btf_type *t)
	332	{
	333	return BTF_INFO_KIND(t->info) == BTF_KIND_TYPEDEF;
	334	}
	335
23da464d KKD	336	static inline bool btf_type_is_volatile(const struct btf_type *t)
	337	{
	338	return BTF_INFO_KIND(t->info) == BTF_KIND_VOLATILE;
	339	}
	340
38207291 MKL	341	static inline bool btf_type_is_func(const struct btf_type *t)
	342	{
	343	return BTF_INFO_KIND(t->info) == BTF_KIND_FUNC;
	344	}
	345
	346	static inline bool btf_type_is_func_proto(const struct btf_type *t)
	347	{
	348	return BTF_INFO_KIND(t->info) == BTF_KIND_FUNC_PROTO;
	349	}
	350
4976b718 HL	351	static inline bool btf_type_is_var(const struct btf_type *t)
	352	{
	353	return BTF_INFO_KIND(t->info) == BTF_KIND_VAR;
	354	}
	355
c6f1bfe8 YS	356	static inline bool btf_type_is_type_tag(const struct btf_type *t)
	357	{
	358	return BTF_INFO_KIND(t->info) == BTF_KIND_TYPE_TAG;
	359	}
	360
4976b718 HL	361	/* union is only a special case of struct:
	362	* all its offsetof(member) == 0
	363	*/
	364	static inline bool btf_type_is_struct(const struct btf_type *t)
	365	{
	366	u8 kind = BTF_INFO_KIND(t->info);
	367
	368	return kind == BTF_KIND_STRUCT \|\| kind == BTF_KIND_UNION;
	369	}
	370
00b85860 KKD	371	static inline bool __btf_type_is_struct(const struct btf_type *t)
	372	{
	373	return BTF_INFO_KIND(t->info) == BTF_KIND_STRUCT;
	374	}
	375
	376	static inline bool btf_type_is_array(const struct btf_type *t)
	377	{
	378	return BTF_INFO_KIND(t->info) == BTF_KIND_ARRAY;
	379	}
	380
27ae7997 MKL	381	static inline u16 btf_type_vlen(const struct btf_type *t)
	382	{
	383	return BTF_INFO_VLEN(t->info);
	384	}
	385
29db4bea AS	386	static inline u16 btf_vlen(const struct btf_type *t)
	387	{
	388	return btf_type_vlen(t);
	389	}
	390
be8704ff AS	391	static inline u16 btf_func_linkage(const struct btf_type *t)
	392	{
	393	return BTF_INFO_VLEN(t->info);
	394	}
	395
27ae7997 MKL	396	static inline bool btf_type_kflag(const struct btf_type *t)
	397	{
	398	return BTF_INFO_KFLAG(t->info);
	399	}
	400
8293eb99 AS	401	static inline u32 __btf_member_bit_offset(const struct btf_type *struct_type,
8293eb99 AS	402	const struct btf_member *member)
85d33df3 MKL	403	{
	404	return btf_type_kflag(struct_type) ? BTF_MEMBER_BIT_OFFSET(member->offset)
	405	: member->offset;
	406	}
	407
8293eb99 AS	408	static inline u32 __btf_member_bitfield_size(const struct btf_type *struct_type,
8293eb99 AS	409	const struct btf_member *member)
27ae7997 MKL	410	{
	411	return btf_type_kflag(struct_type) ? BTF_MEMBER_BITFIELD_SIZE(member->offset)
	412	: 0;
	413	}
	414
29db4bea AS	415	static inline struct btf_member btf_members(const struct btf_type t)
	416	{
	417	return (struct btf_member *)(t + 1);
	418	}
	419
	420	static inline u32 btf_member_bit_offset(const struct btf_type *t, u32 member_idx)
	421	{
	422	const struct btf_member *m = btf_members(t) + member_idx;
	423
	424	return __btf_member_bit_offset(t, m);
	425	}
	426
	427	static inline u32 btf_member_bitfield_size(const struct btf_type *t, u32 member_idx)
	428	{
	429	const struct btf_member *m = btf_members(t) + member_idx;
	430
	431	return __btf_member_bitfield_size(t, m);
	432	}
	433
27ae7997 MKL	434	static inline const struct btf_member btf_type_member(const struct btf_type t)
	435	{
	436	return (const struct btf_member *)(t + 1);
	437	}
	438
29db4bea AS	439	static inline struct btf_array btf_array(const struct btf_type t)
	440	{
	441	return (struct btf_array *)(t + 1);
	442	}
	443
	444	static inline struct btf_enum btf_enum(const struct btf_type t)
	445	{
	446	return (struct btf_enum *)(t + 1);
	447	}
	448
6089fb32 YS	449	static inline struct btf_enum64 btf_enum64(const struct btf_type t)
	450	{
	451	return (struct btf_enum64 *)(t + 1);
	452	}
	453
eaa6bcb7 HL	454	static inline const struct btf_var_secinfo *btf_type_var_secinfo(
	455	const struct btf_type *t)
	456	{
	457	return (const struct btf_var_secinfo *)(t + 1);
	458	}
	459
e70e13e7 MC	460	static inline struct btf_param btf_params(const struct btf_type t)
	461	{
	462	return (struct btf_param *)(t + 1);
	463	}
	464
8ffa5cc1 KKD	465	static inline int btf_id_cmp_func(const void a, const void b)
	466	{
	467	const int pa = a, pb = b;
	468
	469	return pa - pb;
	470	}
	471
	472	static inline bool btf_id_set_contains(const struct btf_id_set *set, u32 id)
	473	{
	474	return bsearch(&id, set->ids, set->cnt, sizeof(u32), btf_id_cmp_func) != NULL;
	475	}
	476
	477	static inline void btf_id_set8_contains(const struct btf_id_set8 set, u32 id)
	478	{
	479	return bsearch(&id, set->pairs, set->cnt, sizeof(set->pairs[0]), btf_id_cmp_func);
	480	}
	481
22dc4a0f	482	struct bpf_prog;
00b85860	483	struct bpf_verifier_log;
22dc4a0f	484
00b85860	485	#ifdef CONFIG_BPF_SYSCALL
838e9690 YS	486	const struct btf_type btf_type_by_id(const struct btf btf, u32 type_id);
838e9690 YS	487	const char btf_name_by_offset(const struct btf btf, u32 offset);
8580ac94	488	struct btf *btf_parse_vmlinux(void);
5b92a28a	489	struct btf bpf_prog_get_target_btf(const struct bpf_prog prog);
a4703e31	490	u32 btf_kfunc_id_set_contains(const struct btf btf,
dee872e1	491	enum bpf_prog_type prog_type,
a4703e31	492	u32 kfunc_btf_id);
5b481aca	493	u32 btf_kfunc_is_modify_return(const struct btf btf, u32 kfunc_btf_id);
dee872e1 KKD	494	int register_btf_kfunc_id_set(enum bpf_prog_type prog_type,
dee872e1 KKD	495	const struct btf_kfunc_id_set *s);
5b481aca	496	int register_btf_fmodret_id_set(const struct btf_kfunc_id_set *kset);
5ce937d6 KKD	497	s32 btf_find_dtor_kfunc(struct btf *btf, u32 btf_id);
	498	int register_btf_id_dtor_kfuncs(const struct btf_id_dtor_kfunc *dtors, u32 add_cnt,
	499	struct module *owner);
8ffa5cc1	500	struct btf_struct_meta btf_find_struct_meta(const struct btf btf, u32 btf_id);
00b85860 KKD	501	const struct btf_member *
	502	btf_get_prog_ctx_type(struct bpf_verifier_log log, const struct btf btf,
	503	const struct btf_type *t, enum bpf_prog_type prog_type,
	504	int arg);
fd264ca0	505	int get_kern_ctx_btf_id(struct bpf_verifier_log *log, enum bpf_prog_type prog_type);
00b85860 KKD	506	bool btf_types_are_same(const struct btf *btf1, u32 id1,
00b85860 KKD	507	const struct btf *btf2, u32 id2);
f6161a8f YS	508	#else
	509	static inline const struct btf_type btf_type_by_id(const struct btf btf,
	510	u32 type_id)
	511	{
	512	return NULL;
	513	}
	514	static inline const char btf_name_by_offset(const struct btf btf,
	515	u32 offset)
	516	{
	517	return NULL;
	518	}
a4703e31	519	static inline u32 btf_kfunc_id_set_contains(const struct btf btf,
dee872e1	520	enum bpf_prog_type prog_type,
dee872e1 KKD	521	u32 kfunc_btf_id)
dee872e1 KKD	522	{
a4703e31	523	return NULL;
dee872e1 KKD	524	}
	525	static inline int register_btf_kfunc_id_set(enum bpf_prog_type prog_type,
	526	const struct btf_kfunc_id_set *s)
	527	{
	528	return 0;
	529	}
5ce937d6 KKD	530	static inline s32 btf_find_dtor_kfunc(struct btf *btf, u32 btf_id)
	531	{
	532	return -ENOENT;
	533	}
	534	static inline int register_btf_id_dtor_kfuncs(const struct btf_id_dtor_kfunc *dtors,
	535	u32 add_cnt, struct module *owner)
	536	{
	537	return 0;
	538	}
8ffa5cc1 KKD	539	static inline struct btf_struct_meta btf_find_struct_meta(const struct btf btf, u32 btf_id)
	540	{
	541	return NULL;
	542	}
00b85860 KKD	543	static inline const struct btf_member *
	544	btf_get_prog_ctx_type(struct bpf_verifier_log log, const struct btf btf,
	545	const struct btf_type *t, enum bpf_prog_type prog_type,
	546	int arg)
	547	{
	548	return NULL;
	549	}
fd264ca0 YS	550	static inline int get_kern_ctx_btf_id(struct bpf_verifier_log *log,
	551	enum bpf_prog_type prog_type) {
	552	return -EINVAL;
	553	}
00b85860 KKD	554	static inline bool btf_types_are_same(const struct btf *btf1, u32 id1,
	555	const struct btf *btf2, u32 id2)
	556	{
	557	return false;
	558	}
f6161a8f	559	#endif
eb3f595d	560
eb1f7f71 BT	561	static inline bool btf_type_is_struct_ptr(struct btf btf, const struct btf_type t)
	562	{
	563	if (!btf_type_is_ptr(t))
	564	return false;
	565
	566	t = btf_type_skip_modifiers(btf, t->type, NULL);
	567
	568	return btf_type_is_struct(t);
	569	}
	570
eb3f595d	571	#endif