linux/arch/powerpc/net/bpf_jit.h
Naveen N. Rao c233f5979b powerpc/bpf: Introduce __PPC_SH64()
Introduce __PPC_SH64() as a 64-bit variant to encode shift field in some
of the shift and rotate instructions operating on double-words. Convert
some of the BPF instruction macros to use the same.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-10 13:28:03 +11:00

270 lines
11 KiB
C

/*
* bpf_jit.h: BPF JIT compiler for PPC
*
* Copyright 2011 Matt Evans <matt@ozlabs.org>, IBM Corporation
* 2016 Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
*
* 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
#ifndef __ASSEMBLY__
#include <asm/types.h>
#ifdef PPC64_ELF_ABI_v1
#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_BCTR() EMIT(PPC_INST_BCTR)
#define PPC_MTCTR(r) EMIT(PPC_INST_MTCTR | ___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_RT(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) | IMM_L(i))
#define PPC_STWU(r, base, i) EMIT(PPC_INST_STWU | ___PPC_RS(r) | \
___PPC_RA(base) | IMM_L(i))
#define PPC_STH(r, base, i) EMIT(PPC_INST_STH | ___PPC_RS(r) | \
___PPC_RA(base) | IMM_L(i))
#define PPC_STB(r, base, i) EMIT(PPC_INST_STB | ___PPC_RS(r) | \
___PPC_RA(base) | IMM_L(i))
#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))
#define PPC_LDBRX(r, base, b) EMIT(PPC_INST_LDBRX | ___PPC_RT(r) | \
___PPC_RA(base) | ___PPC_RB(b))
#define PPC_BPF_LDARX(t, a, b, eh) EMIT(PPC_INST_LDARX | ___PPC_RT(t) | \
___PPC_RA(a) | ___PPC_RB(b) | \
__PPC_EH(eh))
#define PPC_BPF_LWARX(t, a, b, eh) EMIT(PPC_INST_LWARX | ___PPC_RT(t) | \
___PPC_RA(a) | ___PPC_RB(b) | \
__PPC_EH(eh))
#define PPC_BPF_STWCX(s, a, b) EMIT(PPC_INST_STWCX | ___PPC_RS(s) | \
___PPC_RA(a) | ___PPC_RB(b))
#define PPC_BPF_STDCX(s, a, b) EMIT(PPC_INST_STDCX | ___PPC_RS(s) | \
___PPC_RA(a) | ___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
#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_CMPW(a, b) EMIT(PPC_INST_CMPW | ___PPC_RA(a) | \
___PPC_RB(b))
#define PPC_CMPD(a, b) EMIT(PPC_INST_CMPD | ___PPC_RA(a) | \
___PPC_RB(b))
#define PPC_CMPLWI(a, i) EMIT(PPC_INST_CMPLWI | ___PPC_RA(a) | IMM_L(i))
#define PPC_CMPLDI(a, i) EMIT(PPC_INST_CMPLDI | ___PPC_RA(a) | IMM_L(i))
#define PPC_CMPLW(a, b) EMIT(PPC_INST_CMPLW | ___PPC_RA(a) | \
___PPC_RB(b))
#define PPC_CMPLD(a, b) EMIT(PPC_INST_CMPLD | ___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_MULD(d, a, b) EMIT(PPC_INST_MULLD | ___PPC_RT(d) | \
___PPC_RA(a) | ___PPC_RB(b))
#define PPC_MULW(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_DIVD(d, a, b) EMIT(PPC_INST_DIVD | ___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_MR(d, a) PPC_OR(d, a, a)
#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_EXTSW(d, a) EMIT(PPC_INST_EXTSW | ___PPC_RA(d) | \
___PPC_RS(a))
#define PPC_SLW(d, a, s) EMIT(PPC_INST_SLW | ___PPC_RA(d) | \
___PPC_RS(a) | ___PPC_RB(s))
#define PPC_SLD(d, a, s) EMIT(PPC_INST_SLD | ___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))
#define PPC_SRD(d, a, s) EMIT(PPC_INST_SRD | ___PPC_RA(d) | \
___PPC_RS(a) | ___PPC_RB(s))
#define PPC_SRAD(d, a, s) EMIT(PPC_INST_SRAD | ___PPC_RA(d) | \
___PPC_RS(a) | ___PPC_RB(s))
#define PPC_SRADI(d, a, i) EMIT(PPC_INST_SRADI | ___PPC_RA(d) | \
___PPC_RS(a) | __PPC_SH64(i))
#define PPC_RLWINM(d, a, i, mb, me) EMIT(PPC_INST_RLWINM | ___PPC_RA(d) | \
___PPC_RS(a) | __PPC_SH(i) | \
__PPC_MB(mb) | __PPC_ME(me))
#define PPC_RLWIMI(d, a, i, mb, me) EMIT(PPC_INST_RLWIMI | ___PPC_RA(d) | \
___PPC_RS(a) | __PPC_SH(i) | \
__PPC_MB(mb) | __PPC_ME(me))
#define PPC_RLDICL(d, a, i, mb) EMIT(PPC_INST_RLDICL | ___PPC_RA(d) | \
___PPC_RS(a) | __PPC_SH64(i) | \
__PPC_MB64(mb))
#define PPC_RLDICR(d, a, i, me) EMIT(PPC_INST_RLDICR | ___PPC_RA(d) | \
___PPC_RS(a) | __PPC_SH64(i) | \
__PPC_ME64(me))
/* slwi = rlwinm Rx, Ry, n, 0, 31-n */
#define PPC_SLWI(d, a, i) PPC_RLWINM(d, a, i, 0, 31-(i))
/* srwi = rlwinm Rx, Ry, 32-n, n, 31 */
#define PPC_SRWI(d, a, i) PPC_RLWINM(d, a, 32-(i), i, 31)
/* sldi = rldicr Rx, Ry, n, 63-n */
#define PPC_SLDI(d, a, i) PPC_RLDICR(d, a, i, 63-(i))
/* sldi = rldicl Rx, Ry, 64-n, n */
#define PPC_SRDI(d, a, i) PPC_RLDICL(d, a, 64-(i), i)
#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))
/* Sign-extended 32-bit immediate load */
#define PPC_LI32(d, i) do { \
if ((int)(uintptr_t)(i) >= -32768 && \
(int)(uintptr_t)(i) < 32768) \
PPC_LI(d, i); \
else { \
PPC_LIS(d, IMM_H(i)); \
if (IMM_L(i)) \
PPC_ORI(d, d, IMM_L(i)); \
} } while(0)
#define PPC_LI64(d, i) do { \
if ((long)(i) >= -2147483648 && \
(long)(i) < 2147483648) \
PPC_LI32(d, i); \
else { \
if (!((uintptr_t)(i) & 0xffff800000000000ULL)) \
PPC_LI(d, ((uintptr_t)(i) >> 32) & 0xffff); \
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
static inline bool is_nearbranch(int offset)
{
return (offset < 32768) && (offset >= -32768);
}
/*
* 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)
#endif
#endif