bpf_jit_comp.c File Reference

#include <linux/moduleloader.h>
#include <asm/cacheflush.h>
#include <linux/netdevice.h>
#include <linux/filter.h>

Go to the source code of this file.

Macros
#define	EMIT(bytes, len)   do { prog = emit_code(prog, bytes, len); } while (0)
#define	EMIT1(b1)   EMIT(b1, 1)
#define	EMIT2(b1, b2)   EMIT((b1) + ((b2) << 8), 2)
#define	EMIT3(b1, b2, b3)   EMIT((b1) + ((b2) << 8) + ((b3) << 16), 3)
#define	EMIT4(b1, b2, b3, b4)   EMIT((b1) + ((b2) << 8) + ((b3) << 16) + ((b4) << 24), 4)
#define	EMIT1_off32(b1, off)   do { EMIT1(b1); EMIT(off, 4);} while (0)
#define	CLEAR_A()   EMIT2(0x31, 0xc0) /* xor %eax,%eax */
#define	CLEAR_X()   EMIT2(0x31, 0xdb) /* xor %ebx,%ebx */
#define	EMIT_JMP(offset)
#define	X86_JB   0x72
#define	X86_JAE   0x73
#define	X86_JE   0x74
#define	X86_JNE   0x75
#define	X86_JBE   0x76
#define	X86_JA   0x77
#define	EMIT_COND_JMP(op, offset)
#define	COND_SEL(CODE, TOP, FOP)
#define	SEEN_DATAREF   1 /* might call external helpers */
#define	SEEN_XREG   2 /* ebx is used */
#define	SEEN_MEM   4 /* use mem[] for temporary storage */
#define	CHOOSE_LOAD_FUNC(K, func)   ((int)K < 0 ? ((int)K >= SKF_LL_OFF ? func##_negative_offset : func) : func##_positive_offset)

Functions
void	bpf_jit_compile (struct sk_filter *fp)
void	bpf_jit_free (struct sk_filter *fp)

Variables
int bpf_jit_enable	__read_mostly
u8	sk_load_word []
u8	sk_load_half []
u8	sk_load_byte []
u8	sk_load_byte_msh []
u8	sk_load_word_positive_offset []
u8	sk_load_half_positive_offset []
u8	sk_load_byte_positive_offset []
u8	sk_load_byte_msh_positive_offset []
u8	sk_load_word_negative_offset []
u8	sk_load_half_negative_offset []
u8	sk_load_byte_negative_offset []
u8	sk_load_byte_msh_negative_offset []

Macro Definition Documentation

#define CHOOSE_LOAD_FUNC	(		K,
			func
	)		((int)K < 0 ? ((int)K >= SKF_LL_OFF ? func##_negative_offset : func) : func##_positive_offset)

Definition at line 123 of file bpf_jit_comp.c.

#define CLEAR_A

(

)

EMIT2(0x31, 0xc0) /* xor %eax,%eax */

Definition at line 59 of file bpf_jit_comp.c.

#define CLEAR_X

(

)

EMIT2(0x31, 0xdb) /* xor %ebx,%ebx */

Definition at line 60 of file bpf_jit_comp.c.

#define COND_SEL	(		CODE,
			TOP,
			FOP
	)

Value:

case CODE:          \
        t_op = TOP;     \
        f_op = FOP;     \
        goto cond_branch

Definition at line 102 of file bpf_jit_comp.c.

#define EMIT	(		bytes,
			len
	)		do { prog = emit_code(prog, bytes, len); } while (0)

Definition at line 51 of file bpf_jit_comp.c.

#define EMIT1

(

b1

)

EMIT(b1, 1)

Definition at line 53 of file bpf_jit_comp.c.

#define EMIT1_off32	(		b1,
			off
	)		do { EMIT1(b1); EMIT(off, 4);} while (0)

Definition at line 57 of file bpf_jit_comp.c.

#define EMIT2	(		b1,
			b2
	)		EMIT((b1) + ((b2) << 8), 2)

Definition at line 54 of file bpf_jit_comp.c.

#define EMIT3	(		b1,
			b2,
			b3
	)		EMIT((b1) + ((b2) << 8) + ((b3) << 16), 3)

Definition at line 55 of file bpf_jit_comp.c.

#define EMIT4	(		b1,
			b2,
			b3,
			b4
	)		EMIT((b1) + ((b2) << 8) + ((b3) << 16) + ((b4) << 24), 4)

Definition at line 56 of file bpf_jit_comp.c.

#define EMIT_COND_JMP	(		op,
			offset
	)

Value:

do {                                \
    if (is_near(offset))                    \
        EMIT2(op, offset); /* jxx .+off8 */     \
    else {                          \
        EMIT2(0x0f, op + 0x10);             \
        EMIT(offset, 4); /* jxx .+off32 */      \
    }                           \
} while (0)

Definition at line 92 of file bpf_jit_comp.c.

#define EMIT_JMP

(

offset

)

Value:

do {                                    \
    if (offset) {                           \
        if (is_near(offset))                    \
            EMIT2(0xeb, offset); /* jmp .+off8 */       \
		else							\
			EMIT1_off32(0xe9, offset); /* jmp .+off32 */ \
    }                               \
} while (0)

Definition at line 72 of file bpf_jit_comp.c.

#define SEEN_DATAREF   1 /* might call external helpers */

Definition at line 109 of file bpf_jit_comp.c.

#define SEEN_MEM   4 /* use mem[] for temporary storage */

Definition at line 111 of file bpf_jit_comp.c.

#define SEEN_XREG   2 /* ebx is used */

Definition at line 110 of file bpf_jit_comp.c.

#define X86_JA   0x77

Definition at line 90 of file bpf_jit_comp.c.

#define X86_JAE   0x73

Definition at line 86 of file bpf_jit_comp.c.

#define X86_JB   0x72

Definition at line 85 of file bpf_jit_comp.c.

#define X86_JBE   0x76

Definition at line 89 of file bpf_jit_comp.c.

#define X86_JE   0x74

Definition at line 87 of file bpf_jit_comp.c.

#define X86_JNE   0x75

Definition at line 88 of file bpf_jit_comp.c.

Function Documentation

void bpf_jit_compile

(

struct sk_filter *

fp

)

Definition at line 126 of file bpf_jit_comp.c.

void bpf_jit_free

(

struct sk_filter *

fp

)

Definition at line 695 of file bpf_jit_comp.c.

Variable Documentation

int bpf_jit_enable __read_mostly

Definition at line 27 of file bpf_jit_comp.c.

u8 sk_load_byte[]

u8 sk_load_byte_msh[]

u8 sk_load_byte_msh_negative_offset[]

u8 sk_load_byte_msh_positive_offset[]

u8 sk_load_byte_negative_offset[]

u8 sk_load_byte_positive_offset[]

u8 sk_load_half[]

u8 sk_load_half_negative_offset[]

u8 sk_load_half_positive_offset[]

u8 sk_load_word[]

u8 sk_load_word_negative_offset[]

u8 sk_load_word_positive_offset[]