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Release 4.7 arch/powerpc/net/bpf_jit.h

Directory: arch/powerpc/net
/* bpf_jit.h: BPF JIT compiler for PPC64
 *
 * Copyright 2011 Matt Evans <matt@ozlabs.org>, IBM Corporation
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; version 2
 * of the License.
 */
#ifndef _BPF_JIT_H

#define _BPF_JIT_H

#ifdef CONFIG_PPC64

#define BPF_PPC_STACK_R3_OFF	48

#define BPF_PPC_STACK_LOCALS	32

#define BPF_PPC_STACK_BASIC	(48+64)

#define BPF_PPC_STACK_SAVE	(18*8)

#define BPF_PPC_STACKFRAME	(BPF_PPC_STACK_BASIC+BPF_PPC_STACK_LOCALS+ \
                                 BPF_PPC_STACK_SAVE)

#define BPF_PPC_SLOWPATH_FRAME	(48+64)
#else

#define BPF_PPC_STACK_R3_OFF	24

#define BPF_PPC_STACK_LOCALS	16

#define BPF_PPC_STACK_BASIC	(24+32)

#define BPF_PPC_STACK_SAVE	(18*4)

#define BPF_PPC_STACKFRAME	(BPF_PPC_STACK_BASIC+BPF_PPC_STACK_LOCALS+ \
                                 BPF_PPC_STACK_SAVE)

#define BPF_PPC_SLOWPATH_FRAME	(24+32)
#endif


#define REG_SZ         (BITS_PER_LONG/8)

/*
 * Generated code register usage:
 *
 * As normal PPC C ABI (e.g. r1=sp, r2=TOC), with:
 *
 * skb          r3      (Entry parameter)
 * A register   r4
 * X register   r5
 * addr param   r6
 * r7-r10       scratch
 * skb->data    r14
 * skb headlen  r15     (skb->len - skb->data_len)
 * m[0]         r16
 * m[...]       ...
 * m[15]        r31
 */

#define r_skb		3

#define r_ret		3

#define r_A		4

#define r_X		5

#define r_addr		6

#define r_scratch1	7

#define r_scratch2	8

#define r_D		14

#define r_HL		15

#define r_M		16

#ifndef __ASSEMBLY__

/*
 * Assembly helpers from arch/powerpc/net/bpf_jit.S:
 */

#define DECLARE_LOAD_FUNC(func)	\
	extern u8 func[], func##_negative_offset[], func##_positive_offset[]


DECLARE_LOAD_FUNC(sk_load_word);

DECLARE_LOAD_FUNC(sk_load_half);

DECLARE_LOAD_FUNC(sk_load_byte);

DECLARE_LOAD_FUNC(sk_load_byte_msh);

#ifdef CONFIG_PPC64

#define FUNCTION_DESCR_SIZE	24
#else

#define FUNCTION_DESCR_SIZE	0
#endif

/*
 * 16-bit immediate helper macros: HA() is for use with sign-extending instrs
 * (e.g. LD, ADDI).  If the bottom 16 bits is "-ve", add another bit into the
 * top half to negate the effect (i.e. 0xffff + 1 = 0x(1)0000).
 */

#define IMM_H(i)		((uintptr_t)(i)>>16)

#define IMM_HA(i)		(((uintptr_t)(i)>>16) +                       \
                                 (((uintptr_t)(i) & 0x8000) >> 15))

#define IMM_L(i)		((uintptr_t)(i) & 0xffff)


#define PLANT_INSTR(d, idx, instr)					      \
	do { if (d) { (d)[idx] = instr; } idx++; } while (0)

#define EMIT(instr)		PLANT_INSTR(image, ctx->idx, instr)


#define PPC_NOP()		EMIT(PPC_INST_NOP)

#define PPC_BLR()		EMIT(PPC_INST_BLR)

#define PPC_BLRL()		EMIT(PPC_INST_BLRL)

#define PPC_MTLR(r)		EMIT(PPC_INST_MTLR | ___PPC_RT(r))

#define PPC_ADDI(d, a, i)	EMIT(PPC_INST_ADDI | ___PPC_RT(d) |           \
                                     ___PPC_RA(a) | IMM_L(i))

#define PPC_MR(d, a)		PPC_OR(d, a, a)

#define PPC_LI(r, i)		PPC_ADDI(r, 0, i)

#define PPC_ADDIS(d, a, i)	EMIT(PPC_INST_ADDIS |                         \
                                     ___PPC_RS(d) | ___PPC_RA(a) | IMM_L(i))

#define PPC_LIS(r, i)		PPC_ADDIS(r, 0, i)

#define PPC_STD(r, base, i)	EMIT(PPC_INST_STD | ___PPC_RS(r) |            \
                                     ___PPC_RA(base) | ((i) & 0xfffc))

#define PPC_STDU(r, base, i)	EMIT(PPC_INST_STDU | ___PPC_RS(r) |           \
                                     ___PPC_RA(base) | ((i) & 0xfffc))

#define PPC_STW(r, base, i)	EMIT(PPC_INST_STW | ___PPC_RS(r) |            \
                                     ___PPC_RA(base) | ((i) & 0xfffc))

#define PPC_STWU(r, base, i)	EMIT(PPC_INST_STWU | ___PPC_RS(r) |           \
                                     ___PPC_RA(base) | ((i) & 0xfffc))


#define PPC_LBZ(r, base, i)	EMIT(PPC_INST_LBZ | ___PPC_RT(r) |            \
                                     ___PPC_RA(base) | IMM_L(i))

#define PPC_LD(r, base, i)	EMIT(PPC_INST_LD | ___PPC_RT(r) |             \
                                     ___PPC_RA(base) | IMM_L(i))

#define PPC_LWZ(r, base, i)	EMIT(PPC_INST_LWZ | ___PPC_RT(r) |            \
                                     ___PPC_RA(base) | IMM_L(i))

#define PPC_LHZ(r, base, i)	EMIT(PPC_INST_LHZ | ___PPC_RT(r) |            \
                                     ___PPC_RA(base) | IMM_L(i))

#define PPC_LHBRX(r, base, b)	EMIT(PPC_INST_LHBRX | ___PPC_RT(r) |          \
                                     ___PPC_RA(base) | ___PPC_RB(b))

#ifdef CONFIG_PPC64

#define PPC_BPF_LL(r, base, i) do { PPC_LD(r, base, i); } while(0)

#define PPC_BPF_STL(r, base, i) do { PPC_STD(r, base, i); } while(0)

#define PPC_BPF_STLU(r, base, i) do { PPC_STDU(r, base, i); } while(0)
#else

#define PPC_BPF_LL(r, base, i) do { PPC_LWZ(r, base, i); } while(0)

#define PPC_BPF_STL(r, base, i) do { PPC_STW(r, base, i); } while(0)

#define PPC_BPF_STLU(r, base, i) do { PPC_STWU(r, base, i); } while(0)
#endif

/* Convenience helpers for the above with 'far' offsets: */

#define PPC_LBZ_OFFS(r, base, i) do { if ((i) < 32768) PPC_LBZ(r, base, i);   \
                else {  PPC_ADDIS(r, base, IMM_HA(i));                        \
                        PPC_LBZ(r, r, IMM_L(i)); } } while(0)


#define PPC_LD_OFFS(r, base, i) do { if ((i) < 32768) PPC_LD(r, base, i);     \
                else {  PPC_ADDIS(r, base, IMM_HA(i));                        \
                        PPC_LD(r, r, IMM_L(i)); } } while(0)


#define PPC_LWZ_OFFS(r, base, i) do { if ((i) < 32768) PPC_LWZ(r, base, i);   \
                else {  PPC_ADDIS(r, base, IMM_HA(i));                        \
                        PPC_LWZ(r, r, IMM_L(i)); } } while(0)


#define PPC_LHZ_OFFS(r, base, i) do { if ((i) < 32768) PPC_LHZ(r, base, i);   \
                else {  PPC_ADDIS(r, base, IMM_HA(i));                        \
                        PPC_LHZ(r, r, IMM_L(i)); } } while(0)

#ifdef CONFIG_PPC64

#define PPC_LL_OFFS(r, base, i) do { PPC_LD_OFFS(r, base, i); } while(0)
#else

#define PPC_LL_OFFS(r, base, i) do { PPC_LWZ_OFFS(r, base, i); } while(0)
#endif

#ifdef CONFIG_SMP
#ifdef CONFIG_PPC64

#define PPC_BPF_LOAD_CPU(r)		\
	do { BUILD_BUG_ON(FIELD_SIZEOF(struct paca_struct, paca_index) != 2);   \
                PPC_LHZ_OFFS(r, 13, offsetof(struct paca_struct, paca_index));          \
        } while (0)
#else

#define PPC_BPF_LOAD_CPU(r)     \
	do { BUILD_BUG_ON(FIELD_SIZEOF(struct thread_info, cpu) != 4);                  \
                PPC_LHZ_OFFS(r, (1 & ~(THREAD_SIZE - 1)),                                                       \
                                offsetof(struct thread_info, cpu));                                                     \
        } while(0)
#endif
#else

#define PPC_BPF_LOAD_CPU(r) do { PPC_LI(r, 0); } while(0)
#endif


#define PPC_CMPWI(a, i)		EMIT(PPC_INST_CMPWI | ___PPC_RA(a) | IMM_L(i))

#define PPC_CMPDI(a, i)		EMIT(PPC_INST_CMPDI | ___PPC_RA(a) | IMM_L(i))

#define PPC_CMPLWI(a, i)	EMIT(PPC_INST_CMPLWI | ___PPC_RA(a) | IMM_L(i))

#define PPC_CMPLW(a, b)		EMIT(PPC_INST_CMPLW | ___PPC_RA(a) | ___PPC_RB(b))


#define PPC_SUB(d, a, b)	EMIT(PPC_INST_SUB | ___PPC_RT(d) |            \
                                     ___PPC_RB(a) | ___PPC_RA(b))

#define PPC_ADD(d, a, b)	EMIT(PPC_INST_ADD | ___PPC_RT(d) |            \
                                     ___PPC_RA(a) | ___PPC_RB(b))

#define PPC_MUL(d, a, b)	EMIT(PPC_INST_MULLW | ___PPC_RT(d) |          \
                                     ___PPC_RA(a) | ___PPC_RB(b))

#define PPC_MULHWU(d, a, b)	EMIT(PPC_INST_MULHWU | ___PPC_RT(d) |         \
                                     ___PPC_RA(a) | ___PPC_RB(b))

#define PPC_MULI(d, a, i)	EMIT(PPC_INST_MULLI | ___PPC_RT(d) |          \
                                     ___PPC_RA(a) | IMM_L(i))

#define PPC_DIVWU(d, a, b)	EMIT(PPC_INST_DIVWU | ___PPC_RT(d) |          \
                                     ___PPC_RA(a) | ___PPC_RB(b))

#define PPC_AND(d, a, b)	EMIT(PPC_INST_AND | ___PPC_RA(d) |            \
                                     ___PPC_RS(a) | ___PPC_RB(b))

#define PPC_ANDI(d, a, i)	EMIT(PPC_INST_ANDI | ___PPC_RA(d) |           \
                                     ___PPC_RS(a) | IMM_L(i))

#define PPC_AND_DOT(d, a, b)	EMIT(PPC_INST_ANDDOT | ___PPC_RA(d) |         \
                                     ___PPC_RS(a) | ___PPC_RB(b))

#define PPC_OR(d, a, b)		EMIT(PPC_INST_OR | ___PPC_RA(d) |             \
                                     ___PPC_RS(a) | ___PPC_RB(b))

#define PPC_ORI(d, a, i)	EMIT(PPC_INST_ORI | ___PPC_RA(d) |            \
                                     ___PPC_RS(a) | IMM_L(i))

#define PPC_ORIS(d, a, i)	EMIT(PPC_INST_ORIS | ___PPC_RA(d) |           \
                                     ___PPC_RS(a) | IMM_L(i))

#define PPC_XOR(d, a, b)	EMIT(PPC_INST_XOR | ___PPC_RA(d) |            \
                                     ___PPC_RS(a) | ___PPC_RB(b))

#define PPC_XORI(d, a, i)	EMIT(PPC_INST_XORI | ___PPC_RA(d) |           \
                                     ___PPC_RS(a) | IMM_L(i))

#define PPC_XORIS(d, a, i)	EMIT(PPC_INST_XORIS | ___PPC_RA(d) |          \
                                     ___PPC_RS(a) | IMM_L(i))

#define PPC_SLW(d, a, s)	EMIT(PPC_INST_SLW | ___PPC_RA(d) |            \
                                     ___PPC_RS(a) | ___PPC_RB(s))

#define PPC_SRW(d, a, s)	EMIT(PPC_INST_SRW | ___PPC_RA(d) |            \
                                     ___PPC_RS(a) | ___PPC_RB(s))
/* slwi = rlwinm Rx, Ry, n, 0, 31-n */

#define PPC_SLWI(d, a, i)	EMIT(PPC_INST_RLWINM | ___PPC_RA(d) |         \
                                     ___PPC_RS(a) | __PPC_SH(i) |             \
                                     __PPC_MB(0) | __PPC_ME(31-(i)))
/* srwi = rlwinm Rx, Ry, 32-n, n, 31 */

#define PPC_SRWI(d, a, i)	EMIT(PPC_INST_RLWINM | ___PPC_RA(d) |         \
                                     ___PPC_RS(a) | __PPC_SH(32-(i)) |        \
                                     __PPC_MB(i) | __PPC_ME(31))
/* sldi = rldicr Rx, Ry, n, 63-n */

#define PPC_SLDI(d, a, i)	EMIT(PPC_INST_RLDICR | ___PPC_RA(d) |         \
                                     ___PPC_RS(a) | __PPC_SH(i) |             \
                                     __PPC_MB(63-(i)) | (((i) & 0x20) >> 4))

#define PPC_NEG(d, a)		EMIT(PPC_INST_NEG | ___PPC_RT(d) | ___PPC_RA(a))

/* Long jump; (unconditional 'branch') */

#define PPC_JMP(dest)		EMIT(PPC_INST_BRANCH |                        \
                                     (((dest) - (ctx->idx * 4)) & 0x03fffffc))
/* "cond" here covers BO:BI fields. */

#define PPC_BCC_SHORT(cond, dest)	EMIT(PPC_INST_BRANCH_COND |           \
                                             (((cond) & 0x3ff) << 16) |       \
                                             (((dest) - (ctx->idx * 4)) &     \
                                              0xfffc))

#define PPC_LI32(d, i)		do { PPC_LI(d, IMM_L(i));                     \
                if ((u32)(uintptr_t)(i) >= 32768) {                           \
                        PPC_ADDIS(d, d, IMM_HA(i));                           \
                } } while(0)

#define PPC_LI64(d, i)		do {                                          \
                if (!((uintptr_t)(i) & 0xffffffff00000000ULL))                \
                        PPC_LI32(d, i);                                       \
                else {                                                        \
                        PPC_LIS(d, ((uintptr_t)(i) >> 48));                   \
                        if ((uintptr_t)(i) & 0x0000ffff00000000ULL)           \
                                PPC_ORI(d, d,                                 \
                                        ((uintptr_t)(i) >> 32) & 0xffff);     \
                        PPC_SLDI(d, d, 32);                                   \
                        if ((uintptr_t)(i) & 0x00000000ffff0000ULL)           \
                                PPC_ORIS(d, d,                                \
                                         ((uintptr_t)(i) >> 16) & 0xffff);    \
                        if ((uintptr_t)(i) & 0x000000000000ffffULL)           \
                                PPC_ORI(d, d, (uintptr_t)(i) & 0xffff);       \
                } } while (0);

#ifdef CONFIG_PPC64

#define PPC_FUNC_ADDR(d,i) do { PPC_LI64(d, i); } while(0)
#else

#define PPC_FUNC_ADDR(d,i) do { PPC_LI32(d, i); } while(0)
#endif


#define PPC_LHBRX_OFFS(r, base, i) \
		do { PPC_LI32(r, i); PPC_LHBRX(r, r, base); } while(0)
#ifdef __LITTLE_ENDIAN__

#define PPC_NTOHS_OFFS(r, base, i)	PPC_LHBRX_OFFS(r, base, i)
#else

#define PPC_NTOHS_OFFS(r, base, i)	PPC_LHZ_OFFS(r, base, i)
#endif


static inline bool is_nearbranch(int offset) { return (offset < 32768) && (offset >= -32768); }

Contributors

PersonTokensPropCommitsCommitProp
matt evansmatt evans24100.00%1100.00%
Total24100.00%1100.00%

/* * The fly in the ointment of code size changing from pass to pass is * avoided by padding the short branch case with a NOP. If code size differs * with different branch reaches we will have the issue of code moving from * one pass to the next and will need a few passes to converge on a stable * state. */ #define PPC_BCC(cond, dest) do { \ if (is_nearbranch((dest) - (ctx->idx * 4))) { \ PPC_BCC_SHORT(cond, dest); \ PPC_NOP(); \ } else { \ /* Flip the 'T or F' bit to invert comparison */ \ PPC_BCC_SHORT(cond ^ COND_CMP_TRUE, (ctx->idx+2)*4); \ PPC_JMP(dest); \ } } while(0) /* To create a branch condition, select a bit of cr0... */ #define CR0_LT 0 #define CR0_GT 1 #define CR0_EQ 2 /* ...and modify BO[3] */ #define COND_CMP_TRUE 0x100 #define COND_CMP_FALSE 0x000 /* Together, they make all required comparisons: */ #define COND_GT (CR0_GT | COND_CMP_TRUE) #define COND_GE (CR0_LT | COND_CMP_FALSE) #define COND_EQ (CR0_EQ | COND_CMP_TRUE) #define COND_NE (CR0_EQ | COND_CMP_FALSE) #define COND_LT (CR0_LT | COND_CMP_TRUE) #define SEEN_DATAREF 0x10000 /* might call external helpers */ #define SEEN_XREG 0x20000 /* X reg is used */ #define SEEN_MEM 0x40000 /* SEEN_MEM+(1<<n) = use mem[n] for temporary * storage */ #define SEEN_MEM_MSK 0x0ffff struct codegen_context { unsigned int seen; unsigned int idx; int pc_ret0; /* bpf index of first RET #0 instruction (if any) */ }; #endif #endif

Overall Contributors

PersonTokensPropCommitsCommitProp
matt evansmatt evans62760.40%111.11%
denis kirjanovdenis kirjanov26925.92%333.33%
philippe bergheaudphilippe bergheaud525.01%111.11%
daniel borkmanndaniel borkmann333.18%111.11%
michael neulingmichael neuling292.79%111.11%
jan seiffertjan seiffert242.31%111.11%
vladimir murzinvladimir murzin40.39%111.11%
Total1038100.00%9100.00%
Directory: arch/powerpc/net
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