[linux-2.6-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 */
#define KF_RCU_PROTECTED (1 << 11) /* kfunc should be protected by rcu cs when they are invoked */

/*
 * 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

#define __bpf_kfunc_start_defs()					       \
	__diag_push();							       \
	__diag_ignore_all("-Wmissing-declarations",			       \
			  "Global kfuncs as their definitions will be in BTF");\
	__diag_ignore_all("-Wmissing-prototypes",			       \
			  "Global kfuncs as their definitions will be in BTF")

#define __bpf_kfunc_end_defs() __diag_pop()
#define __bpf_hook_start() __bpf_kfunc_start_defs()
#define __bpf_hook_end() __bpf_kfunc_end_defs()

/*
 * 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 bpf_prog;

typedef int (*btf_kfunc_filter_t)(const struct bpf_prog *prog, u32 kfunc_id);

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

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);
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);
s32 bpf_find_btf_id(const char *name, u32 kind, struct btf **btf_p);
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_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, u32 kfunc_btf_id,
			       const struct bpf_prog *prog);
u32 *btf_kfunc_is_modify_return(const struct btf *btf, u32 kfunc_btf_id,
				const struct bpf_prog *prog);
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_type *
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,
					     u32 kfunc_btf_id,
					     struct bpf_prog *prog)

{
	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 */
dfab99df	77	#define KF_RCU_PROTECTED (1 << 11) /* kfunc should be protected by rcu cs when they are invoked */
dee872e1	78
57e7c169 DV	79	/*
	80	* Tag marking a kernel function as a kfunc. This is meant to minimize the
	81	* amount of copy-paste that kfunc authors have to include for correctness so
	82	* as to avoid issues such as the compiler inlining or eliding either a static
	83	* kfunc, or a global kfunc in an LTO build.
	84	*/
	85	#define __bpf_kfunc __used noinline
	86
391145ba DM	87	#define __bpf_kfunc_start_defs() \
	88	__diag_push(); \
	89	__diag_ignore_all("-Wmissing-declarations", \
	90	"Global kfuncs as their definitions will be in BTF");\
	91	__diag_ignore_all("-Wmissing-prototypes", \
	92	"Global kfuncs as their definitions will be in BTF")
	93
	94	#define __bpf_kfunc_end_defs() __diag_pop()
15fb6f2b DM	95	#define __bpf_hook_start() __bpf_kfunc_start_defs()
15fb6f2b DM	96	#define __bpf_hook_end() __bpf_kfunc_end_defs()
391145ba	97
b8d31762 RS	98	/*
	99	* Return the name of the passed struct, if exists, or halt the build if for
	100	* example the structure gets renamed. In this way, developers have to revisit
	101	* the code using that structure name, and update it accordingly.
	102	*/
	103	#define stringify_struct(x) \
	104	({ BUILD_BUG_ON(sizeof(struct x) < 0); \
	105	__stringify(x); })
	106
eb3f595d	107	struct btf;
ffa0c1cf	108	struct btf_member;
eb3f595d	109	struct btf_type;
f56a653c	110	union bpf_attr;
31d0bc81	111	struct btf_show;
dee872e1	112	struct btf_id_set;
e924e80e AG	113	struct bpf_prog;
	114
	115	typedef int (btf_kfunc_filter_t)(const struct bpf_prog prog, u32 kfunc_id);
dee872e1 KKD	116
	117	struct btf_kfunc_id_set {
	118	struct module *owner;
a4703e31	119	struct btf_id_set8 *set;
e924e80e	120	btf_kfunc_filter_t filter;
dee872e1	121	};
eb3f595d	122
5ce937d6 KKD	123	struct btf_id_dtor_kfunc {
	124	u32 btf_id;
	125	u32 kfunc_btf_id;
	126	};
	127
8ffa5cc1 KKD	128	struct btf_struct_meta {
	129	u32 btf_id;
	130	struct btf_record *record;
8ffa5cc1 KKD	131	};
	132
	133	struct btf_struct_metas {
	134	u32 cnt;
	135	struct btf_struct_meta types[];
	136	};
	137
60197cfb MKL	138	extern const struct file_operations btf_fops;
60197cfb MKL	139
22dc4a0f	140	void btf_get(struct btf *btf);
f56a653c	141	void btf_put(struct btf *btf);
47a71c1f	142	int btf_new_fd(const union bpf_attr *attr, bpfptr_t uattr, u32 uattr_sz);
f56a653c	143	struct btf *btf_get_by_fd(int fd);
60197cfb MKL	144	int btf_get_info_by_fd(const struct btf *btf,
	145	const union bpf_attr *attr,
	146	union bpf_attr __user *uattr);
eb3f595d MKL	147	/* Figure out the size of a type_id. If type_id is a modifier
	148	* (e.g. const), it will be resolved to find out the type with size.
	149	*
	150	* For example:
	151	* In describing "const void *", type_id is "const" and "const"
	152	* refers to "void ". The return type will be "void ".
	153	*
	154	* If type_id is a simple "int", then return type will be "int".
	155	*
	156	* @btf: struct btf object
	157	* @type_id: Find out the size of type_id. The type_id of the return
	158	* type is set to *type_id.
	159	* @ret_size: It can be NULL. If not NULL, the size of the return
	160	* type is set to *ret_size.
	161	* Return: The btf_type (resolved to another type with size info if needed).
	162	* NULL is returned if type_id itself does not have size info
	163	* (e.g. void) or it cannot be resolved to another type that
	164	* has size info.
	165	* type_id and ret_size will not be changed in the
	166	* NULL return case.
	167	*/
	168	const struct btf_type btf_type_id_size(const struct btf btf,
	169	u32 *type_id,
	170	u32 *ret_size);
31d0bc81 AM	171
	172	/*
	173	* Options to control show behaviour.
	174	* - BTF_SHOW_COMPACT: no formatting around type information
	175	* - BTF_SHOW_NONAME: no struct/union member names/types
	176	* - BTF_SHOW_PTR_RAW: show raw (unobfuscated) pointer values;
	177	* equivalent to %px.
	178	* - BTF_SHOW_ZERO: show zero-valued struct/union members; they
	179	* are not displayed by default
	180	* - BTF_SHOW_UNSAFE: skip use of bpf_probe_read() to safely read
	181	* data before displaying it.
	182	*/
c4d0bfb4 AM	183	#define BTF_SHOW_COMPACT BTF_F_COMPACT
	184	#define BTF_SHOW_NONAME BTF_F_NONAME
	185	#define BTF_SHOW_PTR_RAW BTF_F_PTR_RAW
	186	#define BTF_SHOW_ZERO BTF_F_ZERO
31d0bc81 AM	187	#define BTF_SHOW_UNSAFE (1ULL << 4)
31d0bc81 AM	188
b00b8dae MKL	189	void btf_type_seq_show(const struct btf btf, u32 type_id, void obj,
b00b8dae MKL	190	struct seq_file *m);
eb411377 AM	191	int btf_type_seq_show_flags(const struct btf btf, u32 type_id, void obj,
eb411377 AM	192	struct seq_file *m, u64 flags);
31d0bc81 AM	193
	194	/*
	195	* Copy len bytes of string representation of obj of BTF type_id into buf.
	196	*
	197	* @btf: struct btf object
	198	* @type_id: type id of type obj points to
	199	* @obj: pointer to typed data
	200	* @buf: buffer to write to
	201	* @len: maximum length to write to buf
	202	* @flags: show options (see above)
	203	*
	204	* Return: length that would have been/was copied as per snprintf, or
	205	* negative error.
	206	*/
	207	int btf_type_snprintf_show(const struct btf btf, u32 type_id, void obj,
	208	char *buf, int len, u64 flags);
	209
78958fca	210	int btf_get_fd_by_id(u32 id);
22dc4a0f	211	u32 btf_obj_id(const struct btf *btf);
290248a5	212	bool btf_is_kernel(const struct btf *btf);
541c3bad AN	213	bool btf_is_module(const struct btf *btf);
	214	struct module btf_try_get_module(const struct btf btf);
	215	u32 btf_nr_types(const struct btf *btf);
ffa0c1cf YS	216	bool btf_member_is_reg_int(const struct btf btf, const struct btf_type s,
	217	const struct btf_member *m,
	218	u32 expected_offset, u32 expected_size);
db559117 KKD	219	struct btf_record btf_parse_fields(const struct btf btf, const struct btf_type *t,
db559117 KKD	220	u32 field_mask, u32 value_size);
865ce09a	221	int btf_check_and_fixup_fields(const struct btf btf, struct btf_record rec);
2824ecb7	222	bool btf_type_is_void(const struct btf_type *t);
27ae7997	223	s32 btf_find_by_name_kind(const struct btf btf, const char name, u8 kind);
b1d1e904	224	s32 bpf_find_btf_id(const char name, u32 kind, struct btf *btf_p);
27ae7997 MKL	225	const struct btf_type btf_type_skip_modifiers(const struct btf btf,
	226	u32 id, u32 *res_id);
	227	const struct btf_type btf_type_resolve_ptr(const struct btf btf,
	228	u32 id, u32 *res_id);
	229	const struct btf_type btf_type_resolve_func_ptr(const struct btf btf,
	230	u32 id, u32 *res_id);
85d33df3 MKL	231	const struct btf_type *
85d33df3 MKL	232	btf_resolve_size(const struct btf btf, const struct btf_type type,
6298399b	233	u32 *type_size);
e6ac2450	234	const char btf_type_str(const struct btf_type t);
27ae7997 MKL	235
	236	#define for_each_member(i, struct_type, member) \
	237	for (i = 0, member = btf_type_member(struct_type); \
	238	i < btf_type_vlen(struct_type); \
	239	i++, member++)
f6161a8f	240
eaa6bcb7 HL	241	#define for_each_vsi(i, datasec_type, member) \
	242	for (i = 0, member = btf_type_var_secinfo(datasec_type); \
	243	i < btf_type_vlen(datasec_type); \
	244	i++, member++)
	245
38207291 MKL	246	static inline bool btf_type_is_ptr(const struct btf_type *t)
	247	{
	248	return BTF_INFO_KIND(t->info) == BTF_KIND_PTR;
	249	}
	250
	251	static inline bool btf_type_is_int(const struct btf_type *t)
	252	{
	253	return BTF_INFO_KIND(t->info) == BTF_KIND_INT;
	254	}
	255
a9b59159 JF	256	static inline bool btf_type_is_small_int(const struct btf_type *t)
	257	{
	258	return btf_type_is_int(t) && t->size <= sizeof(u64);
	259	}
	260
49f67f39 IL	261	static inline u8 btf_int_encoding(const struct btf_type *t)
	262	{
	263	return BTF_INT_ENCODING((u32 )(t + 1));
	264	}
	265
	266	static inline bool btf_type_is_signed_int(const struct btf_type *t)
	267	{
	268	return btf_type_is_int(t) && (btf_int_encoding(t) & BTF_INT_SIGNED);
	269	}
	270
38207291 MKL	271	static inline bool btf_type_is_enum(const struct btf_type *t)
	272	{
	273	return BTF_INFO_KIND(t->info) == BTF_KIND_ENUM;
	274	}
	275
6089fb32 YS	276	static inline bool btf_is_any_enum(const struct btf_type *t)
	277	{
	278	return BTF_INFO_KIND(t->info) == BTF_KIND_ENUM \|\|
	279	BTF_INFO_KIND(t->info) == BTF_KIND_ENUM64;
	280	}
	281
	282	static inline bool btf_kind_core_compat(const struct btf_type *t1,
	283	const struct btf_type *t2)
	284	{
	285	return BTF_INFO_KIND(t1->info) == BTF_INFO_KIND(t2->info) \|\|
	286	(btf_is_any_enum(t1) && btf_is_any_enum(t2));
	287	}
	288
29db4bea AS	289	static inline bool str_is_empty(const char *s)
	290	{
	291	return !s \|\| !s[0];
	292	}
	293
	294	static inline u16 btf_kind(const struct btf_type *t)
	295	{
	296	return BTF_INFO_KIND(t->info);
	297	}
	298
	299	static inline bool btf_is_enum(const struct btf_type *t)
	300	{
	301	return btf_kind(t) == BTF_KIND_ENUM;
	302	}
	303
6089fb32 YS	304	static inline bool btf_is_enum64(const struct btf_type *t)
	305	{
	306	return btf_kind(t) == BTF_KIND_ENUM64;
	307	}
	308
	309	static inline u64 btf_enum64_value(const struct btf_enum64 *e)
	310	{
	311	return ((u64)e->val_hi32 << 32) \| e->val_lo32;
	312	}
	313
29db4bea AS	314	static inline bool btf_is_composite(const struct btf_type *t)
	315	{
	316	u16 kind = btf_kind(t);
	317
	318	return kind == BTF_KIND_STRUCT \|\| kind == BTF_KIND_UNION;
	319	}
	320
	321	static inline bool btf_is_array(const struct btf_type *t)
	322	{
	323	return btf_kind(t) == BTF_KIND_ARRAY;
	324	}
	325
	326	static inline bool btf_is_int(const struct btf_type *t)
	327	{
	328	return btf_kind(t) == BTF_KIND_INT;
	329	}
	330
	331	static inline bool btf_is_ptr(const struct btf_type *t)
	332	{
	333	return btf_kind(t) == BTF_KIND_PTR;
	334	}
	335
	336	static inline u8 btf_int_offset(const struct btf_type *t)
	337	{
	338	return BTF_INT_OFFSET((u32 )(t + 1));
	339	}
	340
34747c41 MKL	341	static inline bool btf_type_is_scalar(const struct btf_type *t)
	342	{
	343	return btf_type_is_int(t) \|\| btf_type_is_enum(t);
	344	}
	345
38207291 MKL	346	static inline bool btf_type_is_typedef(const struct btf_type *t)
	347	{
	348	return BTF_INFO_KIND(t->info) == BTF_KIND_TYPEDEF;
	349	}
	350
23da464d KKD	351	static inline bool btf_type_is_volatile(const struct btf_type *t)
	352	{
	353	return BTF_INFO_KIND(t->info) == BTF_KIND_VOLATILE;
	354	}
	355
38207291 MKL	356	static inline bool btf_type_is_func(const struct btf_type *t)
	357	{
	358	return BTF_INFO_KIND(t->info) == BTF_KIND_FUNC;
	359	}
	360
	361	static inline bool btf_type_is_func_proto(const struct btf_type *t)
	362	{
	363	return BTF_INFO_KIND(t->info) == BTF_KIND_FUNC_PROTO;
	364	}
	365
4976b718 HL	366	static inline bool btf_type_is_var(const struct btf_type *t)
	367	{
	368	return BTF_INFO_KIND(t->info) == BTF_KIND_VAR;
	369	}
	370
c6f1bfe8 YS	371	static inline bool btf_type_is_type_tag(const struct btf_type *t)
	372	{
	373	return BTF_INFO_KIND(t->info) == BTF_KIND_TYPE_TAG;
	374	}
	375
4976b718 HL	376	/* union is only a special case of struct:
	377	* all its offsetof(member) == 0
	378	*/
	379	static inline bool btf_type_is_struct(const struct btf_type *t)
	380	{
	381	u8 kind = BTF_INFO_KIND(t->info);
	382
	383	return kind == BTF_KIND_STRUCT \|\| kind == BTF_KIND_UNION;
	384	}
	385
00b85860 KKD	386	static inline bool __btf_type_is_struct(const struct btf_type *t)
	387	{
	388	return BTF_INFO_KIND(t->info) == BTF_KIND_STRUCT;
	389	}
	390
	391	static inline bool btf_type_is_array(const struct btf_type *t)
	392	{
	393	return BTF_INFO_KIND(t->info) == BTF_KIND_ARRAY;
	394	}
	395
27ae7997 MKL	396	static inline u16 btf_type_vlen(const struct btf_type *t)
	397	{
	398	return BTF_INFO_VLEN(t->info);
	399	}
	400
29db4bea AS	401	static inline u16 btf_vlen(const struct btf_type *t)
	402	{
	403	return btf_type_vlen(t);
	404	}
	405
be8704ff AS	406	static inline u16 btf_func_linkage(const struct btf_type *t)
	407	{
	408	return BTF_INFO_VLEN(t->info);
	409	}
	410
27ae7997 MKL	411	static inline bool btf_type_kflag(const struct btf_type *t)
	412	{
	413	return BTF_INFO_KFLAG(t->info);
	414	}
	415
8293eb99 AS	416	static inline u32 __btf_member_bit_offset(const struct btf_type *struct_type,
8293eb99 AS	417	const struct btf_member *member)
85d33df3 MKL	418	{
	419	return btf_type_kflag(struct_type) ? BTF_MEMBER_BIT_OFFSET(member->offset)
	420	: member->offset;
	421	}
	422
8293eb99 AS	423	static inline u32 __btf_member_bitfield_size(const struct btf_type *struct_type,
8293eb99 AS	424	const struct btf_member *member)
27ae7997 MKL	425	{
	426	return btf_type_kflag(struct_type) ? BTF_MEMBER_BITFIELD_SIZE(member->offset)
	427	: 0;
	428	}
	429
29db4bea AS	430	static inline struct btf_member btf_members(const struct btf_type t)
	431	{
	432	return (struct btf_member *)(t + 1);
	433	}
	434
	435	static inline u32 btf_member_bit_offset(const struct btf_type *t, u32 member_idx)
	436	{
	437	const struct btf_member *m = btf_members(t) + member_idx;
	438
	439	return __btf_member_bit_offset(t, m);
	440	}
	441
	442	static inline u32 btf_member_bitfield_size(const struct btf_type *t, u32 member_idx)
	443	{
	444	const struct btf_member *m = btf_members(t) + member_idx;
	445
	446	return __btf_member_bitfield_size(t, m);
	447	}
	448
27ae7997 MKL	449	static inline const struct btf_member btf_type_member(const struct btf_type t)
	450	{
	451	return (const struct btf_member *)(t + 1);
	452	}
	453
29db4bea AS	454	static inline struct btf_array btf_array(const struct btf_type t)
	455	{
	456	return (struct btf_array *)(t + 1);
	457	}
	458
	459	static inline struct btf_enum btf_enum(const struct btf_type t)
	460	{
	461	return (struct btf_enum *)(t + 1);
	462	}
	463
6089fb32 YS	464	static inline struct btf_enum64 btf_enum64(const struct btf_type t)
	465	{
	466	return (struct btf_enum64 *)(t + 1);
	467	}
	468
eaa6bcb7 HL	469	static inline const struct btf_var_secinfo *btf_type_var_secinfo(
	470	const struct btf_type *t)
	471	{
	472	return (const struct btf_var_secinfo *)(t + 1);
	473	}
	474
e70e13e7 MC	475	static inline struct btf_param btf_params(const struct btf_type t)
	476	{
	477	return (struct btf_param *)(t + 1);
	478	}
	479
8ffa5cc1 KKD	480	static inline int btf_id_cmp_func(const void a, const void b)
	481	{
	482	const int pa = a, pb = b;
	483
	484	return pa - pb;
	485	}
	486
	487	static inline bool btf_id_set_contains(const struct btf_id_set *set, u32 id)
	488	{
	489	return bsearch(&id, set->ids, set->cnt, sizeof(u32), btf_id_cmp_func) != NULL;
	490	}
	491
	492	static inline void btf_id_set8_contains(const struct btf_id_set8 set, u32 id)
	493	{
	494	return bsearch(&id, set->pairs, set->cnt, sizeof(set->pairs[0]), btf_id_cmp_func);
	495	}
	496
00b85860	497	struct bpf_verifier_log;
22dc4a0f	498
00b85860	499	#ifdef CONFIG_BPF_SYSCALL
838e9690 YS	500	const struct btf_type btf_type_by_id(const struct btf btf, u32 type_id);
838e9690 YS	501	const char btf_name_by_offset(const struct btf btf, u32 offset);
8580ac94	502	struct btf *btf_parse_vmlinux(void);
5b92a28a	503	struct btf bpf_prog_get_target_btf(const struct bpf_prog prog);
e924e80e AG	504	u32 btf_kfunc_id_set_contains(const struct btf btf, u32 kfunc_btf_id,
	505	const struct bpf_prog *prog);
	506	u32 btf_kfunc_is_modify_return(const struct btf btf, u32 kfunc_btf_id,
	507	const struct bpf_prog *prog);
dee872e1 KKD	508	int register_btf_kfunc_id_set(enum bpf_prog_type prog_type,
dee872e1 KKD	509	const struct btf_kfunc_id_set *s);
5b481aca	510	int register_btf_fmodret_id_set(const struct btf_kfunc_id_set *kset);
5ce937d6 KKD	511	s32 btf_find_dtor_kfunc(struct btf *btf, u32 btf_id);
	512	int register_btf_id_dtor_kfuncs(const struct btf_id_dtor_kfunc *dtors, u32 add_cnt,
	513	struct module *owner);
8ffa5cc1	514	struct btf_struct_meta btf_find_struct_meta(const struct btf btf, u32 btf_id);
66967a32	515	const struct btf_type *
00b85860 KKD	516	btf_get_prog_ctx_type(struct bpf_verifier_log log, const struct btf btf,
	517	const struct btf_type *t, enum bpf_prog_type prog_type,
	518	int arg);
fd264ca0	519	int get_kern_ctx_btf_id(struct bpf_verifier_log *log, enum bpf_prog_type prog_type);
00b85860 KKD	520	bool btf_types_are_same(const struct btf *btf1, u32 id1,
00b85860 KKD	521	const struct btf *btf2, u32 id2);
f6161a8f YS	522	#else
	523	static inline const struct btf_type btf_type_by_id(const struct btf btf,
	524	u32 type_id)
	525	{
	526	return NULL;
	527	}
	528	static inline const char btf_name_by_offset(const struct btf btf,
	529	u32 offset)
	530	{
	531	return NULL;
	532	}
a4703e31	533	static inline u32 btf_kfunc_id_set_contains(const struct btf btf,
e924e80e AG	534	u32 kfunc_btf_id,
	535	struct bpf_prog *prog)
	536
dee872e1	537	{
a4703e31	538	return NULL;
dee872e1 KKD	539	}
	540	static inline int register_btf_kfunc_id_set(enum bpf_prog_type prog_type,
	541	const struct btf_kfunc_id_set *s)
	542	{
	543	return 0;
	544	}
5ce937d6 KKD	545	static inline s32 btf_find_dtor_kfunc(struct btf *btf, u32 btf_id)
	546	{
	547	return -ENOENT;
	548	}
	549	static inline int register_btf_id_dtor_kfuncs(const struct btf_id_dtor_kfunc *dtors,
	550	u32 add_cnt, struct module *owner)
	551	{
	552	return 0;
	553	}
8ffa5cc1 KKD	554	static inline struct btf_struct_meta btf_find_struct_meta(const struct btf btf, u32 btf_id)
	555	{
	556	return NULL;
	557	}
00b85860 KKD	558	static inline const struct btf_member *
	559	btf_get_prog_ctx_type(struct bpf_verifier_log log, const struct btf btf,
	560	const struct btf_type *t, enum bpf_prog_type prog_type,
	561	int arg)
	562	{
	563	return NULL;
	564	}
fd264ca0 YS	565	static inline int get_kern_ctx_btf_id(struct bpf_verifier_log *log,
	566	enum bpf_prog_type prog_type) {
	567	return -EINVAL;
	568	}
00b85860 KKD	569	static inline bool btf_types_are_same(const struct btf *btf1, u32 id1,
	570	const struct btf *btf2, u32 id2)
	571	{
	572	return false;
	573	}
f6161a8f	574	#endif
eb3f595d	575
eb1f7f71 BT	576	static inline bool btf_type_is_struct_ptr(struct btf btf, const struct btf_type t)
	577	{
	578	if (!btf_type_is_ptr(t))
	579	return false;
	580
	581	t = btf_type_skip_modifiers(btf, t->type, NULL);
	582
	583	return btf_type_is_struct(t);
	584	}
	585
eb3f595d	586	#endif