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linux/arch/powerpc/net/bpf_jit.h

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net: filter: BPF 'JIT' compiler for PPC64 An implementation of a code generator for BPF programs to speed up packet filtering on PPC64, inspired by Eric Dumazet's x86-64 version. Filter code is generated as an ABI-compliant function in module_alloc()'d mem with stackframe & prologue/epilogue generated if required (simple filters don't need anything more than an li/blr). The filter's local variables, M[], live in registers. Supports all BPF opcodes, although "complicated" loads from negative packet offsets (e.g. SKF_LL_OFF) are not yet supported. There are a couple of further optimisations left for future work; many-pass assembly with branch-reach reduction and a register allocator to push M[] variables into volatile registers would improve the code quality further. This currently supports big-endian 64-bit PowerPC only (but is fairly simple to port to PPC32 or LE!). Enabled in the same way as x86-64: echo 1 > /proc/sys/net/core/bpf_jit_enable Or, enabled with extra debug output: echo 2 > /proc/sys/net/core/bpf_jit_enable Signed-off-by: Matt Evans <matt@ozlabs.org> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-20 15:51:00 +00:00
/* 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
#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)
/*
* 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_D 14
#define r_HL 15
#define r_M 16
#ifndef __ASSEMBLY__
/*
* Assembly helpers from arch/powerpc/net/bpf_jit.S:
*/
bpf jit: Let the powerpc jit handle negative offsets Now the helper function from filter.c for negative offsets is exported, it can be used it in the jit to handle negative offsets. First modify the asm load helper functions to handle: - know positive offsets - know negative offsets - any offset then the compiler can be modified to explicitly use these helper when appropriate. This fixes the case of a negative X register and allows to lift the restriction that bpf programs with negative offsets can't be jited. Tested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Jan Seiffert <kaffeemonster@googlemail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-29 19:02:19 +00:00
#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);
net: filter: BPF 'JIT' compiler for PPC64 An implementation of a code generator for BPF programs to speed up packet filtering on PPC64, inspired by Eric Dumazet's x86-64 version. Filter code is generated as an ABI-compliant function in module_alloc()'d mem with stackframe & prologue/epilogue generated if required (simple filters don't need anything more than an li/blr). The filter's local variables, M[], live in registers. Supports all BPF opcodes, although "complicated" loads from negative packet offsets (e.g. SKF_LL_OFF) are not yet supported. There are a couple of further optimisations left for future work; many-pass assembly with branch-reach reduction and a register allocator to push M[] variables into volatile registers would improve the code quality further. This currently supports big-endian 64-bit PowerPC only (but is fairly simple to port to PPC32 or LE!). Enabled in the same way as x86-64: echo 1 > /proc/sys/net/core/bpf_jit_enable Or, enabled with extra debug output: echo 2 > /proc/sys/net/core/bpf_jit_enable Signed-off-by: Matt Evans <matt@ozlabs.org> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-20 15:51:00 +00:00
#define FUNCTION_DESCR_SIZE 24
/*
* 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)
powerpc: Start using ___PPC_RA/B/S/T where necessary Now have ___PPC_RA/B/S/T we can use it in some places. These are places where we can't use the existing defines which will soon enforce R0-R31 usage. The macros being changed here are being used in inline asm, which can't convert to enforce the R0-R31 usage. bpf_jit uses a mix of both generated and non-generated with the same code, so just convert all these to use the ___PPC_R versions which won't enforce R usage later. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-06-25 13:33:21 +00:00
#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))
net: filter: BPF 'JIT' compiler for PPC64 An implementation of a code generator for BPF programs to speed up packet filtering on PPC64, inspired by Eric Dumazet's x86-64 version. Filter code is generated as an ABI-compliant function in module_alloc()'d mem with stackframe & prologue/epilogue generated if required (simple filters don't need anything more than an li/blr). The filter's local variables, M[], live in registers. Supports all BPF opcodes, although "complicated" loads from negative packet offsets (e.g. SKF_LL_OFF) are not yet supported. There are a couple of further optimisations left for future work; many-pass assembly with branch-reach reduction and a register allocator to push M[] variables into volatile registers would improve the code quality further. This currently supports big-endian 64-bit PowerPC only (but is fairly simple to port to PPC32 or LE!). Enabled in the same way as x86-64: echo 1 > /proc/sys/net/core/bpf_jit_enable Or, enabled with extra debug output: echo 2 > /proc/sys/net/core/bpf_jit_enable Signed-off-by: Matt Evans <matt@ozlabs.org> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-20 15:51:00 +00:00
#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 | \
powerpc: Start using ___PPC_RA/B/S/T where necessary Now have ___PPC_RA/B/S/T we can use it in some places. These are places where we can't use the existing defines which will soon enforce R0-R31 usage. The macros being changed here are being used in inline asm, which can't convert to enforce the R0-R31 usage. bpf_jit uses a mix of both generated and non-generated with the same code, so just convert all these to use the ___PPC_R versions which won't enforce R usage later. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-06-25 13:33:21 +00:00
___PPC_RS(d) | ___PPC_RA(a) | IMM_L(i))
net: filter: BPF 'JIT' compiler for PPC64 An implementation of a code generator for BPF programs to speed up packet filtering on PPC64, inspired by Eric Dumazet's x86-64 version. Filter code is generated as an ABI-compliant function in module_alloc()'d mem with stackframe & prologue/epilogue generated if required (simple filters don't need anything more than an li/blr). The filter's local variables, M[], live in registers. Supports all BPF opcodes, although "complicated" loads from negative packet offsets (e.g. SKF_LL_OFF) are not yet supported. There are a couple of further optimisations left for future work; many-pass assembly with branch-reach reduction and a register allocator to push M[] variables into volatile registers would improve the code quality further. This currently supports big-endian 64-bit PowerPC only (but is fairly simple to port to PPC32 or LE!). Enabled in the same way as x86-64: echo 1 > /proc/sys/net/core/bpf_jit_enable Or, enabled with extra debug output: echo 2 > /proc/sys/net/core/bpf_jit_enable Signed-off-by: Matt Evans <matt@ozlabs.org> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-20 15:51:00 +00:00
#define PPC_LIS(r, i) PPC_ADDIS(r, 0, i)
powerpc: Start using ___PPC_RA/B/S/T where necessary Now have ___PPC_RA/B/S/T we can use it in some places. These are places where we can't use the existing defines which will soon enforce R0-R31 usage. The macros being changed here are being used in inline asm, which can't convert to enforce the R0-R31 usage. bpf_jit uses a mix of both generated and non-generated with the same code, so just convert all these to use the ___PPC_R versions which won't enforce R usage later. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-06-25 13:33:21 +00:00
#define PPC_STD(r, base, i) EMIT(PPC_INST_STD | ___PPC_RS(r) | \
___PPC_RA(base) | ((i) & 0xfffc))
net: filter: BPF 'JIT' compiler for PPC64 An implementation of a code generator for BPF programs to speed up packet filtering on PPC64, inspired by Eric Dumazet's x86-64 version. Filter code is generated as an ABI-compliant function in module_alloc()'d mem with stackframe & prologue/epilogue generated if required (simple filters don't need anything more than an li/blr). The filter's local variables, M[], live in registers. Supports all BPF opcodes, although "complicated" loads from negative packet offsets (e.g. SKF_LL_OFF) are not yet supported. There are a couple of further optimisations left for future work; many-pass assembly with branch-reach reduction and a register allocator to push M[] variables into volatile registers would improve the code quality further. This currently supports big-endian 64-bit PowerPC only (but is fairly simple to port to PPC32 or LE!). Enabled in the same way as x86-64: echo 1 > /proc/sys/net/core/bpf_jit_enable Or, enabled with extra debug output: echo 2 > /proc/sys/net/core/bpf_jit_enable Signed-off-by: Matt Evans <matt@ozlabs.org> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-20 15:51:00 +00:00
powerpc: Start using ___PPC_RA/B/S/T where necessary Now have ___PPC_RA/B/S/T we can use it in some places. These are places where we can't use the existing defines which will soon enforce R0-R31 usage. The macros being changed here are being used in inline asm, which can't convert to enforce the R0-R31 usage. bpf_jit uses a mix of both generated and non-generated with the same code, so just convert all these to use the ___PPC_R versions which won't enforce R usage later. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-06-25 13:33:21 +00:00
#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))
net: filter: BPF 'JIT' compiler for PPC64 An implementation of a code generator for BPF programs to speed up packet filtering on PPC64, inspired by Eric Dumazet's x86-64 version. Filter code is generated as an ABI-compliant function in module_alloc()'d mem with stackframe & prologue/epilogue generated if required (simple filters don't need anything more than an li/blr). The filter's local variables, M[], live in registers. Supports all BPF opcodes, although "complicated" loads from negative packet offsets (e.g. SKF_LL_OFF) are not yet supported. There are a couple of further optimisations left for future work; many-pass assembly with branch-reach reduction and a register allocator to push M[] variables into volatile registers would improve the code quality further. This currently supports big-endian 64-bit PowerPC only (but is fairly simple to port to PPC32 or LE!). Enabled in the same way as x86-64: echo 1 > /proc/sys/net/core/bpf_jit_enable Or, enabled with extra debug output: echo 2 > /proc/sys/net/core/bpf_jit_enable Signed-off-by: Matt Evans <matt@ozlabs.org> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-20 15:51:00 +00:00
/* Convenience helpers for the above with 'far' offsets: */
#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)
powerpc: Start using ___PPC_RA/B/S/T where necessary Now have ___PPC_RA/B/S/T we can use it in some places. These are places where we can't use the existing defines which will soon enforce R0-R31 usage. The macros being changed here are being used in inline asm, which can't convert to enforce the R0-R31 usage. bpf_jit uses a mix of both generated and non-generated with the same code, so just convert all these to use the ___PPC_R versions which won't enforce R usage later. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-06-25 13:33:21 +00:00
#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))
net: filter: BPF 'JIT' compiler for PPC64 An implementation of a code generator for BPF programs to speed up packet filtering on PPC64, inspired by Eric Dumazet's x86-64 version. Filter code is generated as an ABI-compliant function in module_alloc()'d mem with stackframe & prologue/epilogue generated if required (simple filters don't need anything more than an li/blr). The filter's local variables, M[], live in registers. Supports all BPF opcodes, although "complicated" loads from negative packet offsets (e.g. SKF_LL_OFF) are not yet supported. There are a couple of further optimisations left for future work; many-pass assembly with branch-reach reduction and a register allocator to push M[] variables into volatile registers would improve the code quality further. This currently supports big-endian 64-bit PowerPC only (but is fairly simple to port to PPC32 or LE!). Enabled in the same way as x86-64: echo 1 > /proc/sys/net/core/bpf_jit_enable Or, enabled with extra debug output: echo 2 > /proc/sys/net/core/bpf_jit_enable Signed-off-by: Matt Evans <matt@ozlabs.org> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-20 15:51:00 +00:00
powerpc: Start using ___PPC_RA/B/S/T where necessary Now have ___PPC_RA/B/S/T we can use it in some places. These are places where we can't use the existing defines which will soon enforce R0-R31 usage. The macros being changed here are being used in inline asm, which can't convert to enforce the R0-R31 usage. bpf_jit uses a mix of both generated and non-generated with the same code, so just convert all these to use the ___PPC_R versions which won't enforce R usage later. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-06-25 13:33:21 +00:00
#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))
PPC: net: bpf_jit_comp: add XOR instruction for BPF JIT This patch is a follow-up for patch "filter: add XOR instruction for use with X/K" that implements BPF PowerPC JIT parts for the BPF XOR operation. Signed-off-by: Daniel Borkmann <daniel.borkmann@tik.ee.ethz.ch> Cc: Matt Evans <matt@ozlabs.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Matt Evans <matt@ozlabs.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-08 11:39:41 +00:00
#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))
powerpc: Start using ___PPC_RA/B/S/T where necessary Now have ___PPC_RA/B/S/T we can use it in some places. These are places where we can't use the existing defines which will soon enforce R0-R31 usage. The macros being changed here are being used in inline asm, which can't convert to enforce the R0-R31 usage. bpf_jit uses a mix of both generated and non-generated with the same code, so just convert all these to use the ___PPC_R versions which won't enforce R usage later. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-06-25 13:33:21 +00:00
#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))
net: filter: BPF 'JIT' compiler for PPC64 An implementation of a code generator for BPF programs to speed up packet filtering on PPC64, inspired by Eric Dumazet's x86-64 version. Filter code is generated as an ABI-compliant function in module_alloc()'d mem with stackframe & prologue/epilogue generated if required (simple filters don't need anything more than an li/blr). The filter's local variables, M[], live in registers. Supports all BPF opcodes, although "complicated" loads from negative packet offsets (e.g. SKF_LL_OFF) are not yet supported. There are a couple of further optimisations left for future work; many-pass assembly with branch-reach reduction and a register allocator to push M[] variables into volatile registers would improve the code quality further. This currently supports big-endian 64-bit PowerPC only (but is fairly simple to port to PPC32 or LE!). Enabled in the same way as x86-64: echo 1 > /proc/sys/net/core/bpf_jit_enable Or, enabled with extra debug output: echo 2 > /proc/sys/net/core/bpf_jit_enable Signed-off-by: Matt Evans <matt@ozlabs.org> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-20 15:51:00 +00:00
/* slwi = rlwinm Rx, Ry, n, 0, 31-n */
powerpc: Start using ___PPC_RA/B/S/T where necessary Now have ___PPC_RA/B/S/T we can use it in some places. These are places where we can't use the existing defines which will soon enforce R0-R31 usage. The macros being changed here are being used in inline asm, which can't convert to enforce the R0-R31 usage. bpf_jit uses a mix of both generated and non-generated with the same code, so just convert all these to use the ___PPC_R versions which won't enforce R usage later. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-06-25 13:33:21 +00:00
#define PPC_SLWI(d, a, i) EMIT(PPC_INST_RLWINM | ___PPC_RA(d) | \
___PPC_RS(a) | __PPC_SH(i) | \
net: filter: BPF 'JIT' compiler for PPC64 An implementation of a code generator for BPF programs to speed up packet filtering on PPC64, inspired by Eric Dumazet's x86-64 version. Filter code is generated as an ABI-compliant function in module_alloc()'d mem with stackframe & prologue/epilogue generated if required (simple filters don't need anything more than an li/blr). The filter's local variables, M[], live in registers. Supports all BPF opcodes, although "complicated" loads from negative packet offsets (e.g. SKF_LL_OFF) are not yet supported. There are a couple of further optimisations left for future work; many-pass assembly with branch-reach reduction and a register allocator to push M[] variables into volatile registers would improve the code quality further. This currently supports big-endian 64-bit PowerPC only (but is fairly simple to port to PPC32 or LE!). Enabled in the same way as x86-64: echo 1 > /proc/sys/net/core/bpf_jit_enable Or, enabled with extra debug output: echo 2 > /proc/sys/net/core/bpf_jit_enable Signed-off-by: Matt Evans <matt@ozlabs.org> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-20 15:51:00 +00:00
__PPC_MB(0) | __PPC_ME(31-(i)))
/* srwi = rlwinm Rx, Ry, 32-n, n, 31 */
powerpc: Start using ___PPC_RA/B/S/T where necessary Now have ___PPC_RA/B/S/T we can use it in some places. These are places where we can't use the existing defines which will soon enforce R0-R31 usage. The macros being changed here are being used in inline asm, which can't convert to enforce the R0-R31 usage. bpf_jit uses a mix of both generated and non-generated with the same code, so just convert all these to use the ___PPC_R versions which won't enforce R usage later. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-06-25 13:33:21 +00:00
#define PPC_SRWI(d, a, i) EMIT(PPC_INST_RLWINM | ___PPC_RA(d) | \
___PPC_RS(a) | __PPC_SH(32-(i)) | \
net: filter: BPF 'JIT' compiler for PPC64 An implementation of a code generator for BPF programs to speed up packet filtering on PPC64, inspired by Eric Dumazet's x86-64 version. Filter code is generated as an ABI-compliant function in module_alloc()'d mem with stackframe & prologue/epilogue generated if required (simple filters don't need anything more than an li/blr). The filter's local variables, M[], live in registers. Supports all BPF opcodes, although "complicated" loads from negative packet offsets (e.g. SKF_LL_OFF) are not yet supported. There are a couple of further optimisations left for future work; many-pass assembly with branch-reach reduction and a register allocator to push M[] variables into volatile registers would improve the code quality further. This currently supports big-endian 64-bit PowerPC only (but is fairly simple to port to PPC32 or LE!). Enabled in the same way as x86-64: echo 1 > /proc/sys/net/core/bpf_jit_enable Or, enabled with extra debug output: echo 2 > /proc/sys/net/core/bpf_jit_enable Signed-off-by: Matt Evans <matt@ozlabs.org> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-20 15:51:00 +00:00
__PPC_MB(i) | __PPC_ME(31))
/* sldi = rldicr Rx, Ry, n, 63-n */
powerpc: Start using ___PPC_RA/B/S/T where necessary Now have ___PPC_RA/B/S/T we can use it in some places. These are places where we can't use the existing defines which will soon enforce R0-R31 usage. The macros being changed here are being used in inline asm, which can't convert to enforce the R0-R31 usage. bpf_jit uses a mix of both generated and non-generated with the same code, so just convert all these to use the ___PPC_R versions which won't enforce R usage later. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-06-25 13:33:21 +00:00
#define PPC_SLDI(d, a, i) EMIT(PPC_INST_RLDICR | ___PPC_RA(d) | \
___PPC_RS(a) | __PPC_SH(i) | \
net: filter: BPF 'JIT' compiler for PPC64 An implementation of a code generator for BPF programs to speed up packet filtering on PPC64, inspired by Eric Dumazet's x86-64 version. Filter code is generated as an ABI-compliant function in module_alloc()'d mem with stackframe & prologue/epilogue generated if required (simple filters don't need anything more than an li/blr). The filter's local variables, M[], live in registers. Supports all BPF opcodes, although "complicated" loads from negative packet offsets (e.g. SKF_LL_OFF) are not yet supported. There are a couple of further optimisations left for future work; many-pass assembly with branch-reach reduction and a register allocator to push M[] variables into volatile registers would improve the code quality further. This currently supports big-endian 64-bit PowerPC only (but is fairly simple to port to PPC32 or LE!). Enabled in the same way as x86-64: echo 1 > /proc/sys/net/core/bpf_jit_enable Or, enabled with extra debug output: echo 2 > /proc/sys/net/core/bpf_jit_enable Signed-off-by: Matt Evans <matt@ozlabs.org> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-20 15:51:00 +00:00
__PPC_MB(63-(i)) | (((i) & 0x20) >> 4))
powerpc: Start using ___PPC_RA/B/S/T where necessary Now have ___PPC_RA/B/S/T we can use it in some places. These are places where we can't use the existing defines which will soon enforce R0-R31 usage. The macros being changed here are being used in inline asm, which can't convert to enforce the R0-R31 usage. bpf_jit uses a mix of both generated and non-generated with the same code, so just convert all these to use the ___PPC_R versions which won't enforce R usage later. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-06-25 13:33:21 +00:00
#define PPC_NEG(d, a) EMIT(PPC_INST_NEG | ___PPC_RT(d) | ___PPC_RA(a))
net: filter: BPF 'JIT' compiler for PPC64 An implementation of a code generator for BPF programs to speed up packet filtering on PPC64, inspired by Eric Dumazet's x86-64 version. Filter code is generated as an ABI-compliant function in module_alloc()'d mem with stackframe & prologue/epilogue generated if required (simple filters don't need anything more than an li/blr). The filter's local variables, M[], live in registers. Supports all BPF opcodes, although "complicated" loads from negative packet offsets (e.g. SKF_LL_OFF) are not yet supported. There are a couple of further optimisations left for future work; many-pass assembly with branch-reach reduction and a register allocator to push M[] variables into volatile registers would improve the code quality further. This currently supports big-endian 64-bit PowerPC only (but is fairly simple to port to PPC32 or LE!). Enabled in the same way as x86-64: echo 1 > /proc/sys/net/core/bpf_jit_enable Or, enabled with extra debug output: echo 2 > /proc/sys/net/core/bpf_jit_enable Signed-off-by: Matt Evans <matt@ozlabs.org> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-20 15:51:00 +00:00
/* 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);
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)
#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
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