[linux-2.6-block.git] / include / linux / bpf.h

/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
 *
 * 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>

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_free)(struct bpf_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);
	int (*map_delete_elem)(struct bpf_map *map, void *key);
};

struct bpf_map {
	atomic_t refcnt;
	enum bpf_map_type map_type;
	u32 key_size;
	u32 value_size;
	u32 max_entries;
	struct bpf_map_ops *ops;
	struct work_struct work;
};

struct bpf_map_type_list {
	struct list_head list_node;
	struct bpf_map_ops *ops;
	enum bpf_map_type type;
};

void bpf_register_map_type(struct bpf_map_type_list *tl);
void bpf_map_put(struct bpf_map *map);
struct bpf_map *bpf_map_get(struct fd f);

/* function argument constraints */
enum bpf_arg_type {
	ARG_ANYTHING = 0,	/* any argument is ok */

	/* 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_STACK,	/* any pointer to eBPF program stack */
	ARG_CONST_STACK_SIZE,	/* number of bytes accessed from stack */
};

/* 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;
	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 {
	BPF_READ = 1,
	BPF_WRITE = 2
};

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);
};

struct bpf_prog_type_list {
	struct list_head list_node;
	struct bpf_verifier_ops *ops;
	enum bpf_prog_type type;
};

void bpf_register_prog_type(struct bpf_prog_type_list *tl);

struct bpf_prog;

struct bpf_prog_aux {
	atomic_t refcnt;
	bool is_gpl_compatible;
	enum bpf_prog_type prog_type;
	struct bpf_verifier_ops *ops;
	struct bpf_map **used_maps;
	u32 used_map_cnt;
	struct bpf_prog *prog;
	struct work_struct work;
};

void bpf_prog_put(struct bpf_prog *prog);
struct bpf_prog *bpf_prog_get(u32 ufd);
/* verify correctness of eBPF program */
int bpf_check(struct bpf_prog *fp, union bpf_attr *attr);

#endif /* _LINUX_BPF_H */
Commit	Line	Data
99c55f7d AS	1	/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
	2	*
	3	* This program is free software; you can redistribute it and/or
	4	* modify it under the terms of version 2 of the GNU General Public
	5	* License as published by the Free Software Foundation.
	6	*/
	7	#ifndef _LINUX_BPF_H
	8	#define _LINUX_BPF_H 1
	9
	10	#include <uapi/linux/bpf.h>
	11	#include <linux/workqueue.h>
db20fd2b	12	#include <linux/file.h>
99c55f7d AS	13
	14	struct bpf_map;
	15
	16	/* map is generic key/value storage optionally accesible by eBPF programs */
	17	struct bpf_map_ops {
	18	/* funcs callable from userspace (via syscall) */
	19	struct bpf_map (map_alloc)(union bpf_attr *attr);
	20	void (map_free)(struct bpf_map );
db20fd2b AS	21	int (map_get_next_key)(struct bpf_map map, void key, void next_key);
	22
	23	/* funcs callable from userspace and from eBPF programs */
	24	void (map_lookup_elem)(struct bpf_map map, void key);
	25	int (map_update_elem)(struct bpf_map map, void key, void value);
	26	int (map_delete_elem)(struct bpf_map map, void *key);
99c55f7d AS	27	};
	28
	29	struct bpf_map {
	30	atomic_t refcnt;
	31	enum bpf_map_type map_type;
	32	u32 key_size;
	33	u32 value_size;
	34	u32 max_entries;
	35	struct bpf_map_ops *ops;
	36	struct work_struct work;
	37	};
	38
	39	struct bpf_map_type_list {
	40	struct list_head list_node;
	41	struct bpf_map_ops *ops;
	42	enum bpf_map_type type;
	43	};
	44
	45	void bpf_register_map_type(struct bpf_map_type_list *tl);
	46	void bpf_map_put(struct bpf_map *map);
db20fd2b	47	struct bpf_map *bpf_map_get(struct fd f);
99c55f7d	48
17a52670 AS	49	/* function argument constraints */
	50	enum bpf_arg_type {
	51	ARG_ANYTHING = 0, /* any argument is ok */
	52
	53	/* the following constraints used to prototype
	54	* bpf_map_lookup/update/delete_elem() functions
	55	*/
	56	ARG_CONST_MAP_PTR, /* const argument used as pointer to bpf_map */
	57	ARG_PTR_TO_MAP_KEY, /* pointer to stack used as map key */
	58	ARG_PTR_TO_MAP_VALUE, /* pointer to stack used as map value */
	59
	60	/* the following constraints used to prototype bpf_memcmp() and other
	61	* functions that access data on eBPF program stack
	62	*/
	63	ARG_PTR_TO_STACK, /* any pointer to eBPF program stack */
	64	ARG_CONST_STACK_SIZE, /* number of bytes accessed from stack */
	65	};
	66
	67	/* type of values returned from helper functions */
	68	enum bpf_return_type {
	69	RET_INTEGER, /* function returns integer */
	70	RET_VOID, /* function doesn't return anything */
	71	RET_PTR_TO_MAP_VALUE_OR_NULL, /* returns a pointer to map elem value or NULL */
	72	};
	73
09756af4 AS	74	/* eBPF function prototype used by verifier to allow BPF_CALLs from eBPF programs
	75	* to in-kernel helper functions and for adjusting imm32 field in BPF_CALL
	76	* instructions after verifying
	77	*/
	78	struct bpf_func_proto {
	79	u64 (*func)(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
	80	bool gpl_only;
17a52670 AS	81	enum bpf_return_type ret_type;
	82	enum bpf_arg_type arg1_type;
	83	enum bpf_arg_type arg2_type;
	84	enum bpf_arg_type arg3_type;
	85	enum bpf_arg_type arg4_type;
	86	enum bpf_arg_type arg5_type;
	87	};
	88
	89	/* bpf_context is intentionally undefined structure. Pointer to bpf_context is
	90	* the first argument to eBPF programs.
	91	* For socket filters: 'struct bpf_context ' == 'struct sk_buff '
	92	*/
	93	struct bpf_context;
	94
	95	enum bpf_access_type {
	96	BPF_READ = 1,
	97	BPF_WRITE = 2
09756af4 AS	98	};
	99
	100	struct bpf_verifier_ops {
	101	/* return eBPF function prototype for verification */
	102	const struct bpf_func_proto (get_func_proto)(enum bpf_func_id func_id);
17a52670 AS	103
	104	/* return true if 'size' wide access at offset 'off' within bpf_context
	105	* with 'type' (read or write) is allowed
	106	*/
	107	bool (*is_valid_access)(int off, int size, enum bpf_access_type type);
09756af4 AS	108	};
	109
	110	struct bpf_prog_type_list {
	111	struct list_head list_node;
	112	struct bpf_verifier_ops *ops;
	113	enum bpf_prog_type type;
	114	};
	115
	116	void bpf_register_prog_type(struct bpf_prog_type_list *tl);
	117
	118	struct bpf_prog;
	119
	120	struct bpf_prog_aux {
	121	atomic_t refcnt;
	122	bool is_gpl_compatible;
	123	enum bpf_prog_type prog_type;
	124	struct bpf_verifier_ops *ops;
	125	struct bpf_map **used_maps;
	126	u32 used_map_cnt;
	127	struct bpf_prog *prog;
	128	struct work_struct work;
	129	};
	130
	131	void bpf_prog_put(struct bpf_prog *prog);
	132	struct bpf_prog *bpf_prog_get(u32 ufd);
51580e79 AS	133	/* verify correctness of eBPF program */
51580e79 AS	134	int bpf_check(struct bpf_prog fp, union bpf_attr attr);
09756af4	135
99c55f7d	136	#endif /* _LINUX_BPF_H */