From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758199AbaGOG3u (ORCPT ); Tue, 15 Jul 2014 02:29:50 -0400 Received: from mail-pd0-f175.google.com ([209.85.192.175]:45049 "EHLO mail-pd0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757616AbaGOGZc (ORCPT ); Tue, 15 Jul 2014 02:25:32 -0400 From: Zi Shen Lim To: Catalin Marinas , Will Deacon , Jiang Liu , AKASHI Takahiro , "David S. Miller" , Daniel Borkmann , Alexei Starovoitov Cc: Zi Shen Lim , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, netdev@vger.kernel.org Subject: [PATCH RFCv3 01/14] arm64: introduce aarch64_insn_gen_comp_branch_imm() Date: Mon, 14 Jul 2014 23:24:59 -0700 Message-Id: <1405405512-4423-2-git-send-email-zlim.lnx@gmail.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1405405512-4423-1-git-send-email-zlim.lnx@gmail.com> References: <1405405512-4423-1-git-send-email-zlim.lnx@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Introduce function to generate compare & branch (immediate) instructions. Signed-off-by: Zi Shen Lim --- arch/arm64/include/asm/insn.h | 57 ++++++++++++++++++++++++++++ arch/arm64/kernel/insn.c | 86 ++++++++++++++++++++++++++++++++++++++++--- 2 files changed, 138 insertions(+), 5 deletions(-) diff --git a/arch/arm64/include/asm/insn.h b/arch/arm64/include/asm/insn.h index dc1f73b..a98c495 100644 --- a/arch/arm64/include/asm/insn.h +++ b/arch/arm64/include/asm/insn.h @@ -2,6 +2,8 @@ * Copyright (C) 2013 Huawei Ltd. * Author: Jiang Liu * + * Copyright (C) 2014 Zi Shen Lim + * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. @@ -67,9 +69,58 @@ enum aarch64_insn_imm_type { AARCH64_INSN_IMM_MAX }; +enum aarch64_insn_register_type { + AARCH64_INSN_REGTYPE_RT, +}; + +enum aarch64_insn_register { + AARCH64_INSN_REG_0 = 0, + AARCH64_INSN_REG_1 = 1, + AARCH64_INSN_REG_2 = 2, + AARCH64_INSN_REG_3 = 3, + AARCH64_INSN_REG_4 = 4, + AARCH64_INSN_REG_5 = 5, + AARCH64_INSN_REG_6 = 6, + AARCH64_INSN_REG_7 = 7, + AARCH64_INSN_REG_8 = 8, + AARCH64_INSN_REG_9 = 9, + AARCH64_INSN_REG_10 = 10, + AARCH64_INSN_REG_11 = 11, + AARCH64_INSN_REG_12 = 12, + AARCH64_INSN_REG_13 = 13, + AARCH64_INSN_REG_14 = 14, + AARCH64_INSN_REG_15 = 15, + AARCH64_INSN_REG_16 = 16, + AARCH64_INSN_REG_17 = 17, + AARCH64_INSN_REG_18 = 18, + AARCH64_INSN_REG_19 = 19, + AARCH64_INSN_REG_20 = 20, + AARCH64_INSN_REG_21 = 21, + AARCH64_INSN_REG_22 = 22, + AARCH64_INSN_REG_23 = 23, + AARCH64_INSN_REG_24 = 24, + AARCH64_INSN_REG_25 = 25, + AARCH64_INSN_REG_26 = 26, + AARCH64_INSN_REG_27 = 27, + AARCH64_INSN_REG_28 = 28, + AARCH64_INSN_REG_29 = 29, + AARCH64_INSN_REG_FP = 29, /* Frame pointer */ + AARCH64_INSN_REG_30 = 30, + AARCH64_INSN_REG_LR = 30, /* Link register */ + AARCH64_INSN_REG_ZR = 31, /* Zero: as source register */ + AARCH64_INSN_REG_SP = 31 /* Stack pointer: as load/store base reg */ +}; + +enum aarch64_insn_variant { + AARCH64_INSN_VARIANT_32BIT, + AARCH64_INSN_VARIANT_64BIT +}; + enum aarch64_insn_branch_type { AARCH64_INSN_BRANCH_NOLINK, AARCH64_INSN_BRANCH_LINK, + AARCH64_INSN_BRANCH_COMP_ZERO, + AARCH64_INSN_BRANCH_COMP_NONZERO, }; #define __AARCH64_INSN_FUNCS(abbr, mask, val) \ @@ -80,6 +131,8 @@ static __always_inline u32 aarch64_insn_get_##abbr##_value(void) \ __AARCH64_INSN_FUNCS(b, 0xFC000000, 0x14000000) __AARCH64_INSN_FUNCS(bl, 0xFC000000, 0x94000000) +__AARCH64_INSN_FUNCS(cbz, 0xFE000000, 0x34000000) +__AARCH64_INSN_FUNCS(cbnz, 0xFE000000, 0x35000000) __AARCH64_INSN_FUNCS(svc, 0xFFE0001F, 0xD4000001) __AARCH64_INSN_FUNCS(hvc, 0xFFE0001F, 0xD4000002) __AARCH64_INSN_FUNCS(smc, 0xFFE0001F, 0xD4000003) @@ -97,6 +150,10 @@ u32 aarch64_insn_encode_immediate(enum aarch64_insn_imm_type type, u32 insn, u64 imm); u32 aarch64_insn_gen_branch_imm(unsigned long pc, unsigned long addr, enum aarch64_insn_branch_type type); +u32 aarch64_insn_gen_comp_branch_imm(unsigned long pc, unsigned long addr, + enum aarch64_insn_register reg, + enum aarch64_insn_variant variant, + enum aarch64_insn_branch_type type); u32 aarch64_insn_gen_hint(enum aarch64_insn_hint_op op); u32 aarch64_insn_gen_nop(void); diff --git a/arch/arm64/kernel/insn.c b/arch/arm64/kernel/insn.c index 92f3683..d01bb4e 100644 --- a/arch/arm64/kernel/insn.c +++ b/arch/arm64/kernel/insn.c @@ -2,6 +2,8 @@ * Copyright (C) 2013 Huawei Ltd. * Author: Jiang Liu * + * Copyright (C) 2014 Zi Shen Lim + * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. @@ -264,10 +266,36 @@ u32 __kprobes aarch64_insn_encode_immediate(enum aarch64_insn_imm_type type, return insn; } -u32 __kprobes aarch64_insn_gen_branch_imm(unsigned long pc, unsigned long addr, - enum aarch64_insn_branch_type type) +static u32 aarch64_insn_encode_register(enum aarch64_insn_register_type type, + u32 insn, + enum aarch64_insn_register reg) +{ + int shift; + + if (reg < AARCH64_INSN_REG_0 || reg > AARCH64_INSN_REG_SP) { + pr_err("%s: unknown register encoding %d\n", __func__, reg); + return 0; + } + + switch (type) { + case AARCH64_INSN_REGTYPE_RT: + shift = 0; + break; + default: + pr_err("%s: unknown register type encoding %d\n", __func__, + type); + return 0; + } + + insn &= ~(GENMASK(4, 0) << shift); + insn |= reg << shift; + + return insn; +} + +static inline long branch_imm_common(unsigned long pc, unsigned long addr, + long range) { - u32 insn; long offset; /* @@ -276,13 +304,24 @@ u32 __kprobes aarch64_insn_gen_branch_imm(unsigned long pc, unsigned long addr, */ BUG_ON((pc & 0x3) || (addr & 0x3)); + offset = ((long)addr - (long)pc); + BUG_ON(offset < -range || offset >= range); + + return offset; +} + +u32 __kprobes aarch64_insn_gen_branch_imm(unsigned long pc, unsigned long addr, + enum aarch64_insn_branch_type type) +{ + u32 insn; + long offset; + /* * B/BL support [-128M, 128M) offset * ARM64 virtual address arrangement guarantees all kernel and module * texts are within +/-128M. */ - offset = ((long)addr - (long)pc); - BUG_ON(offset < -SZ_128M || offset >= SZ_128M); + offset = branch_imm_common(pc, addr, SZ_128M); if (type == AARCH64_INSN_BRANCH_LINK) insn = aarch64_insn_get_bl_value(); @@ -293,6 +332,43 @@ u32 __kprobes aarch64_insn_gen_branch_imm(unsigned long pc, unsigned long addr, offset >> 2); } +u32 aarch64_insn_gen_comp_branch_imm(unsigned long pc, unsigned long addr, + enum aarch64_insn_register reg, + enum aarch64_insn_variant variant, + enum aarch64_insn_branch_type type) +{ + u32 insn; + long offset; + + offset = branch_imm_common(pc, addr, SZ_1M); + + switch (type) { + case AARCH64_INSN_BRANCH_COMP_ZERO: + insn = aarch64_insn_get_cbz_value(); + break; + case AARCH64_INSN_BRANCH_COMP_NONZERO: + insn = aarch64_insn_get_cbnz_value(); + break; + default: + BUG_ON(1); + } + + switch (variant) { + case AARCH64_INSN_VARIANT_32BIT: + break; + case AARCH64_INSN_VARIANT_64BIT: + insn |= BIT(31); + break; + default: + BUG_ON(1); + } + + insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RT, insn, reg); + + return aarch64_insn_encode_immediate(AARCH64_INSN_IMM_19, insn, + offset >> 2); +} + u32 __kprobes aarch64_insn_gen_hint(enum aarch64_insn_hint_op op) { return aarch64_insn_get_hint_value() | op; -- 1.9.1