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Release 4.12 include/linux/bpf.h

Directory: include/linux
/* Copyright (c) 2011-2014 PLUMgrid,
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of version 2 of the GNU General Public
 * License as published by the Free Software Foundation.
#ifndef _LINUX_BPF_H

#define _LINUX_BPF_H 1

#include <uapi/linux/bpf.h>

#include <linux/workqueue.h>
#include <linux/file.h>
#include <linux/percpu.h>
#include <linux/err.h>
#include <linux/rbtree_latch.h>

struct perf_event;
struct bpf_map;

/* map is generic key/value storage optionally accesible by eBPF programs */

struct bpf_map_ops {
	/* funcs callable from userspace (via syscall) */
struct bpf_map *(*map_alloc)(union bpf_attr *attr);
void (*map_release)(struct bpf_map *map, struct file *map_file);
void (*map_free)(struct bpf_map *map);
int (*map_get_next_key)(struct bpf_map *map, void *key, void *next_key);

	/* funcs callable from userspace and from eBPF programs */
void *(*map_lookup_elem)(struct bpf_map *map, void *key);
int (*map_update_elem)(struct bpf_map *map, void *key, void *value, u64 flags);
int (*map_delete_elem)(struct bpf_map *map, void *key);

	/* funcs called by prog_array and perf_event_array map */
void *(*map_fd_get_ptr)(struct bpf_map *map, struct file *map_file,
				int fd);
void (*map_fd_put_ptr)(void *ptr);
u32 (*map_gen_lookup)(struct bpf_map *map, struct bpf_insn *insn_buf);

struct bpf_map {
atomic_t refcnt;
enum bpf_map_type map_type;
u32 key_size;
u32 value_size;
u32 max_entries;
u32 map_flags;
u32 pages;
struct user_struct *user;
const struct bpf_map_ops *ops;
struct work_struct work;
atomic_t usercnt;
struct bpf_map *inner_map_meta;

/* function argument constraints */

enum bpf_arg_type {
ARG_DONTCARE = 0,	/* unused argument in helper function */

	/* the following constraints used to prototype
         * bpf_map_lookup/update/delete_elem() functions
ARG_CONST_MAP_PTR,	/* const argument used as pointer to bpf_map */
ARG_PTR_TO_MAP_KEY,	/* pointer to stack used as map key */
ARG_PTR_TO_MAP_VALUE,	/* pointer to stack used as map value */

	/* the following constraints used to prototype bpf_memcmp() and other
         * functions that access data on eBPF program stack
ARG_PTR_TO_MEM,		/* pointer to valid memory (stack, packet, map value) */
ARG_PTR_TO_UNINIT_MEM,	/* pointer to memory does not need to be initialized,
                                 * helper function must fill all bytes or clear
                                 * them in error case.

ARG_CONST_SIZE,		/* number of bytes accessed from memory */
ARG_CONST_SIZE_OR_ZERO,	/* number of bytes accessed from memory or 0 */

ARG_PTR_TO_CTX,		/* pointer to context */
ARG_ANYTHING,		/* any (initialized) argument is ok */

/* type of values returned from helper functions */

enum bpf_return_type {
RET_INTEGER,			/* function returns integer */
RET_VOID,			/* function doesn't return anything */
RET_PTR_TO_MAP_VALUE_OR_NULL,	/* returns a pointer to map elem value or NULL */

/* eBPF function prototype used by verifier to allow BPF_CALLs from eBPF programs
 * to in-kernel helper functions and for adjusting imm32 field in BPF_CALL
 * instructions after verifying

struct bpf_func_proto {
u64 (*func)(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
bool gpl_only;
bool pkt_access;
enum bpf_return_type ret_type;
enum bpf_arg_type arg1_type;
enum bpf_arg_type arg2_type;
enum bpf_arg_type arg3_type;
enum bpf_arg_type arg4_type;
enum bpf_arg_type arg5_type;

/* bpf_context is intentionally undefined structure. Pointer to bpf_context is
 * the first argument to eBPF programs.
 * For socket filters: 'struct bpf_context *' == 'struct sk_buff *'
struct bpf_context;

enum bpf_access_type {

/* types of values stored in eBPF registers */

enum bpf_reg_type {
NOT_INIT = 0,		 /* nothing was written into register */
UNKNOWN_VALUE,		 /* reg doesn't contain a valid pointer */
PTR_TO_CTX,		 /* reg points to bpf_context */
CONST_PTR_TO_MAP,	 /* reg points to struct bpf_map */
PTR_TO_MAP_VALUE,	 /* reg points to map element value */
PTR_TO_MAP_VALUE_OR_NULL,/* points to map elem value or NULL */
FRAME_PTR,		 /* reg == frame_pointer */
PTR_TO_STACK,		 /* reg == frame_pointer + imm */
CONST_IMM,		 /* constant integer value */

	/* PTR_TO_PACKET represents:
         * skb->data
         * skb->data + imm
         * skb->data + (u16) var
         * skb->data + (u16) var + imm
         * if (range > 0) then [ptr, ptr + range - off) is safe to access
         * if (id > 0) means that some 'var' was added
         * if (off > 0) menas that 'imm' was added
PTR_TO_PACKET_END,	 /* skb->data + headlen */

	/* PTR_TO_MAP_VALUE_ADJ is used for doing pointer math inside of a map
         * elem value.  We only allow this if we can statically verify that
         * access from this register are going to fall within the size of the
         * map element.

struct bpf_prog;

struct bpf_verifier_ops {
	/* return eBPF function prototype for verification */
const struct bpf_func_proto *(*get_func_proto)(enum bpf_func_id func_id);

	/* return true if 'size' wide access at offset 'off' within bpf_context
         * with 'type' (read or write) is allowed
bool (*is_valid_access)(int off, int size, enum bpf_access_type type,
				enum bpf_reg_type *reg_type);
int (*gen_prologue)(struct bpf_insn *insn, bool direct_write,
			    const struct bpf_prog *prog);
u32 (*convert_ctx_access)(enum bpf_access_type type,
				  const struct bpf_insn *src,
				  struct bpf_insn *dst,
				  struct bpf_prog *prog);
int (*test_run)(struct bpf_prog *prog, const union bpf_attr *kattr,
			union bpf_attr __user *uattr);

struct bpf_prog_aux {
atomic_t refcnt;
u32 used_map_cnt;
u32 max_ctx_offset;
struct latch_tree_node ksym_tnode;
struct list_head ksym_lnode;
const struct bpf_verifier_ops *ops;
struct bpf_map **used_maps;
struct bpf_prog *prog;
struct user_struct *user;
	union {
struct work_struct work;
struct rcu_head	rcu;

struct bpf_array {
struct bpf_map map;
u32 elem_size;
	/* 'ownership' of prog_array is claimed by the first program that
         * is going to use this map or by the first program which FD is stored
         * in the map to make sure that all callers and callees have the same
         * prog_type and JITed flag
enum bpf_prog_type owner_prog_type;
bool owner_jited;
	union {
		char value[0] __aligned(8);
		void *ptrs[0] __aligned(8);
		void __percpu *pptrs[0] __aligned(8);

#define MAX_TAIL_CALL_CNT 32

struct bpf_event_entry {
struct perf_event *event;
struct file *perf_file;
struct file *map_file;
struct rcu_head rcu;

u64 bpf_tail_call(u64 ctx, u64 r2, u64 index, u64 r4, u64 r5);
u64 bpf_get_stackid(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);

bool bpf_prog_array_compatible(struct bpf_array *array, const struct bpf_prog *fp);
int bpf_prog_calc_tag(struct bpf_prog *fp);

const struct bpf_func_proto *bpf_get_trace_printk_proto(void);

typedef unsigned long (*bpf_ctx_copy_t)(void *dst, const void *src,
					unsigned long off, unsigned long len);

u64 bpf_event_output(struct bpf_map *map, u64 flags, void *meta, u64 meta_size,
		     void *ctx, u64 ctx_size, bpf_ctx_copy_t ctx_copy);

int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr,
			  union bpf_attr __user *uattr);
int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr,
			  union bpf_attr __user *uattr);

DECLARE_PER_CPU(int, bpf_prog_active);

#define BPF_PROG_TYPE(_id, _ops) \
	extern const struct bpf_verifier_ops _ops;

#define BPF_MAP_TYPE(_id, _ops) \
	extern const struct bpf_map_ops _ops;
#include <linux/bpf_types.h>



struct bpf_prog *bpf_prog_get(u32 ufd);
struct bpf_prog *bpf_prog_get_type(u32 ufd, enum bpf_prog_type type);
struct bpf_prog * __must_check bpf_prog_add(struct bpf_prog *prog, int i);
void bpf_prog_sub(struct bpf_prog *prog, int i);
struct bpf_prog * __must_check bpf_prog_inc(struct bpf_prog *prog);
void bpf_prog_put(struct bpf_prog *prog);
int __bpf_prog_charge(struct user_struct *user, u32 pages);
void __bpf_prog_uncharge(struct user_struct *user, u32 pages);

struct bpf_map *bpf_map_get_with_uref(u32 ufd);
struct bpf_map *__bpf_map_get(struct fd f);
struct bpf_map * __must_check bpf_map_inc(struct bpf_map *map, bool uref);
void bpf_map_put_with_uref(struct bpf_map *map);
void bpf_map_put(struct bpf_map *map);
int bpf_map_precharge_memlock(u32 pages);
void *bpf_map_area_alloc(size_t size);
void bpf_map_area_free(void *base);

extern int sysctl_unprivileged_bpf_disabled;

int bpf_map_new_fd(struct bpf_map *map);
int bpf_prog_new_fd(struct bpf_prog *prog);

int bpf_obj_pin_user(u32 ufd, const char __user *pathname);
int bpf_obj_get_user(const char __user *pathname);

int bpf_percpu_hash_copy(struct bpf_map *map, void *key, void *value);
int bpf_percpu_array_copy(struct bpf_map *map, void *key, void *value);
int bpf_percpu_hash_update(struct bpf_map *map, void *key, void *value,
			   u64 flags);
int bpf_percpu_array_update(struct bpf_map *map, void *key, void *value,
			    u64 flags);

int bpf_stackmap_copy(struct bpf_map *map, void *key, void *value);

int bpf_fd_array_map_update_elem(struct bpf_map *map, struct file *map_file,
				 void *key, void *value, u64 map_flags);
void bpf_fd_array_map_clear(struct bpf_map *map);
int bpf_fd_htab_map_update_elem(struct bpf_map *map, struct file *map_file,
				void *key, void *value, u64 map_flags);

/* memcpy that is used with 8-byte aligned pointers, power-of-8 size and
 * forced to use 'long' read/writes to try to atomically copy long counters.
 * Best-effort only.  No barriers here, since it _will_ race with concurrent
 * updates from BPF programs. Called from bpf syscall and mostly used with
 * size 8 or 16 bytes, so ask compiler to inline it.

static inline void bpf_long_memcpy(void *dst, const void *src, u32 size) { const long *lsrc = src; long *ldst = dst; size /= sizeof(long); while (size--) *ldst++ = *lsrc++; }


Alexei Starovoitov52100.00%1100.00%

/* verify correctness of eBPF program */ int bpf_check(struct bpf_prog **fp, union bpf_attr *attr); #else
static inline struct bpf_prog *bpf_prog_get(u32 ufd) { return ERR_PTR(-EOPNOTSUPP); }


Daniel Borkmann1157.89%150.00%
Alexei Starovoitov842.11%150.00%

static inline struct bpf_prog *bpf_prog_get_type(u32 ufd, enum bpf_prog_type type) { return ERR_PTR(-EOPNOTSUPP); }


Daniel Borkmann23100.00%1100.00%

static inline struct bpf_prog * __must_check bpf_prog_add(struct bpf_prog *prog, int i) { return ERR_PTR(-EOPNOTSUPP); }


Brenden Blanco2496.00%150.00%
Daniel Borkmann14.00%150.00%

static inline void bpf_prog_sub(struct bpf_prog *prog, int i) { }


Daniel Borkmann14100.00%1100.00%

static inline void bpf_prog_put(struct bpf_prog *prog) { }


Daniel Borkmann11100.00%1100.00%

static inline struct bpf_prog * __must_check bpf_prog_inc(struct bpf_prog *prog) { return ERR_PTR(-EOPNOTSUPP); }


Alexei Starovoitov2195.45%150.00%
Daniel Borkmann14.55%150.00%

static inline int __bpf_prog_charge(struct user_struct *user, u32 pages) { return 0; }


Daniel Borkmann18100.00%1100.00%

static inline void __bpf_prog_uncharge(struct user_struct *user, u32 pages) { }


Daniel Borkmann14100.00%1100.00%

#endif /* CONFIG_BPF_SYSCALL */ /* verifier prototypes for helper functions called from eBPF programs */ extern const struct bpf_func_proto bpf_map_lookup_elem_proto; extern const struct bpf_func_proto bpf_map_update_elem_proto; extern const struct bpf_func_proto bpf_map_delete_elem_proto; extern const struct bpf_func_proto bpf_get_prandom_u32_proto; extern const struct bpf_func_proto bpf_get_smp_processor_id_proto; extern const struct bpf_func_proto bpf_get_numa_node_id_proto; extern const struct bpf_func_proto bpf_tail_call_proto; extern const struct bpf_func_proto bpf_ktime_get_ns_proto; extern const struct bpf_func_proto bpf_get_current_pid_tgid_proto; extern const struct bpf_func_proto bpf_get_current_uid_gid_proto; extern const struct bpf_func_proto bpf_get_current_comm_proto; extern const struct bpf_func_proto bpf_skb_vlan_push_proto; extern const struct bpf_func_proto bpf_skb_vlan_pop_proto; extern const struct bpf_func_proto bpf_get_stackid_proto; /* Shared helpers among cBPF and eBPF. */ void bpf_user_rnd_init_once(void); u64 bpf_user_rnd_u32(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5); #endif /* _LINUX_BPF_H */

Overall Contributors

Alexei Starovoitov92057.68%3243.84%
Daniel Borkmann54434.11%3243.84%
Brenden Blanco382.38%22.74%
Wang Nan301.88%11.37%
Martin KaFai Lau301.88%22.74%
Johannes Berg271.69%22.74%
Josef Bacik30.19%11.37%
Zi Shen Lim30.19%11.37%
Directory: include/linux
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