It would make some sense to share the conditional execution code between 32 and 64bit. In order to achieve this, let's move that code to virt/kvm/arm/aarch32.c. While we're at it, drop a superfluous BUG_ON() that wasn't that useful. Following patches will migrate the 32bit port to that code base. Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx> --- arch/arm/kvm/emulate.c | 4 +- arch/arm64/kvm/Makefile | 3 +- arch/arm64/kvm/emulate.c | 148 ----------------------------------------------- virt/kvm/arm/aarch32.c | 146 ++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 149 insertions(+), 152 deletions(-) delete mode 100644 arch/arm64/kvm/emulate.c create mode 100644 virt/kvm/arm/aarch32.c diff --git a/arch/arm/kvm/emulate.c b/arch/arm/kvm/emulate.c index af93e3f..eda9ddd 100644 --- a/arch/arm/kvm/emulate.c +++ b/arch/arm/kvm/emulate.c @@ -221,9 +221,7 @@ static void kvm_adjust_itstate(struct kvm_vcpu *vcpu) unsigned long cpsr = *vcpu_cpsr(vcpu); bool is_arm = !(cpsr & PSR_T_BIT); - BUG_ON(is_arm && (cpsr & PSR_IT_MASK)); - - if (!(cpsr & PSR_IT_MASK)) + if (is_arm || !(cpsr & PSR_IT_MASK)) return; cond = (cpsr & 0xe000) >> 13; diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile index 695eb3c..d50a82a 100644 --- a/arch/arm64/kvm/Makefile +++ b/arch/arm64/kvm/Makefile @@ -16,9 +16,10 @@ kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/e kvm-$(CONFIG_KVM_ARM_HOST) += $(ARM)/arm.o $(ARM)/mmu.o $(ARM)/mmio.o kvm-$(CONFIG_KVM_ARM_HOST) += $(ARM)/psci.o $(ARM)/perf.o -kvm-$(CONFIG_KVM_ARM_HOST) += emulate.o inject_fault.o regmap.o +kvm-$(CONFIG_KVM_ARM_HOST) += inject_fault.o regmap.o kvm-$(CONFIG_KVM_ARM_HOST) += hyp.o hyp-init.o handle_exit.o kvm-$(CONFIG_KVM_ARM_HOST) += guest.o debug.o reset.o sys_regs.o sys_regs_generic_v8.o +kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/aarch32.o kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic/vgic.o kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic/vgic-init.o diff --git a/arch/arm64/kvm/emulate.c b/arch/arm64/kvm/emulate.c deleted file mode 100644 index 40098ad..0000000 --- a/arch/arm64/kvm/emulate.c +++ /dev/null @@ -1,148 +0,0 @@ -/* - * (not much of an) Emulation layer for 32bit guests. - * - * Copyright (C) 2012,2013 - ARM Ltd - * Author: Marc Zyngier <marc.zyngier@xxxxxxx> - * - * based on arch/arm/kvm/emulate.c - * Copyright (C) 2012 - Virtual Open Systems and Columbia University - * Author: Christoffer Dall <c.dall@xxxxxxxxxxxxxxxxxxxxxx> - * - * 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. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program. If not, see <http://www.gnu.org/licenses/>. - */ - -#include <linux/kvm_host.h> -#include <asm/kvm_emulate.h> - -/* - * stolen from arch/arm/kernel/opcodes.c - * - * condition code lookup table - * index into the table is test code: EQ, NE, ... LT, GT, AL, NV - * - * bit position in short is condition code: NZCV - */ -static const unsigned short cc_map[16] = { - 0xF0F0, /* EQ == Z set */ - 0x0F0F, /* NE */ - 0xCCCC, /* CS == C set */ - 0x3333, /* CC */ - 0xFF00, /* MI == N set */ - 0x00FF, /* PL */ - 0xAAAA, /* VS == V set */ - 0x5555, /* VC */ - 0x0C0C, /* HI == C set && Z clear */ - 0xF3F3, /* LS == C clear || Z set */ - 0xAA55, /* GE == (N==V) */ - 0x55AA, /* LT == (N!=V) */ - 0x0A05, /* GT == (!Z && (N==V)) */ - 0xF5FA, /* LE == (Z || (N!=V)) */ - 0xFFFF, /* AL always */ - 0 /* NV */ -}; - -/* - * Check if a trapped instruction should have been executed or not. - */ -bool kvm_condition_valid32(const struct kvm_vcpu *vcpu) -{ - unsigned long cpsr; - u32 cpsr_cond; - int cond; - - /* Top two bits non-zero? Unconditional. */ - if (kvm_vcpu_get_hsr(vcpu) >> 30) - return true; - - /* Is condition field valid? */ - cond = kvm_vcpu_get_condition(vcpu); - if (cond == 0xE) - return true; - - cpsr = *vcpu_cpsr(vcpu); - - if (cond < 0) { - /* This can happen in Thumb mode: examine IT state. */ - unsigned long it; - - it = ((cpsr >> 8) & 0xFC) | ((cpsr >> 25) & 0x3); - - /* it == 0 => unconditional. */ - if (it == 0) - return true; - - /* The cond for this insn works out as the top 4 bits. */ - cond = (it >> 4); - } - - cpsr_cond = cpsr >> 28; - - if (!((cc_map[cond] >> cpsr_cond) & 1)) - return false; - - return true; -} - -/** - * adjust_itstate - adjust ITSTATE when emulating instructions in IT-block - * @vcpu: The VCPU pointer - * - * When exceptions occur while instructions are executed in Thumb IF-THEN - * blocks, the ITSTATE field of the CPSR is not advanced (updated), so we have - * to do this little bit of work manually. The fields map like this: - * - * IT[7:0] -> CPSR[26:25],CPSR[15:10] - */ -static void kvm_adjust_itstate(struct kvm_vcpu *vcpu) -{ - unsigned long itbits, cond; - unsigned long cpsr = *vcpu_cpsr(vcpu); - bool is_arm = !(cpsr & COMPAT_PSR_T_BIT); - - BUG_ON(is_arm && (cpsr & COMPAT_PSR_IT_MASK)); - - if (!(cpsr & COMPAT_PSR_IT_MASK)) - return; - - cond = (cpsr & 0xe000) >> 13; - itbits = (cpsr & 0x1c00) >> (10 - 2); - itbits |= (cpsr & (0x3 << 25)) >> 25; - - /* Perform ITAdvance (see page A2-52 in ARM DDI 0406C) */ - if ((itbits & 0x7) == 0) - itbits = cond = 0; - else - itbits = (itbits << 1) & 0x1f; - - cpsr &= ~COMPAT_PSR_IT_MASK; - cpsr |= cond << 13; - cpsr |= (itbits & 0x1c) << (10 - 2); - cpsr |= (itbits & 0x3) << 25; - *vcpu_cpsr(vcpu) = cpsr; -} - -/** - * kvm_skip_instr - skip a trapped instruction and proceed to the next - * @vcpu: The vcpu pointer - */ -void kvm_skip_instr32(struct kvm_vcpu *vcpu, bool is_wide_instr) -{ - bool is_thumb; - - is_thumb = !!(*vcpu_cpsr(vcpu) & COMPAT_PSR_T_BIT); - if (is_thumb && !is_wide_instr) - *vcpu_pc(vcpu) += 2; - else - *vcpu_pc(vcpu) += 4; - kvm_adjust_itstate(vcpu); -} diff --git a/virt/kvm/arm/aarch32.c b/virt/kvm/arm/aarch32.c new file mode 100644 index 0000000..cb02e56 --- /dev/null +++ b/virt/kvm/arm/aarch32.c @@ -0,0 +1,146 @@ +/* + * (not much of an) Emulation layer for 32bit guests. + * + * Copyright (C) 2012,2013 - ARM Ltd + * Author: Marc Zyngier <marc.zyngier@xxxxxxx> + * + * based on arch/arm/kvm/emulate.c + * Copyright (C) 2012 - Virtual Open Systems and Columbia University + * Author: Christoffer Dall <c.dall@xxxxxxxxxxxxxxxxxxxxxx> + * + * 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/kvm_host.h> +#include <asm/kvm_emulate.h> + +/* + * stolen from arch/arm/kernel/opcodes.c + * + * condition code lookup table + * index into the table is test code: EQ, NE, ... LT, GT, AL, NV + * + * bit position in short is condition code: NZCV + */ +static const unsigned short cc_map[16] = { + 0xF0F0, /* EQ == Z set */ + 0x0F0F, /* NE */ + 0xCCCC, /* CS == C set */ + 0x3333, /* CC */ + 0xFF00, /* MI == N set */ + 0x00FF, /* PL */ + 0xAAAA, /* VS == V set */ + 0x5555, /* VC */ + 0x0C0C, /* HI == C set && Z clear */ + 0xF3F3, /* LS == C clear || Z set */ + 0xAA55, /* GE == (N==V) */ + 0x55AA, /* LT == (N!=V) */ + 0x0A05, /* GT == (!Z && (N==V)) */ + 0xF5FA, /* LE == (Z || (N!=V)) */ + 0xFFFF, /* AL always */ + 0 /* NV */ +}; + +/* + * Check if a trapped instruction should have been executed or not. + */ +bool kvm_condition_valid32(const struct kvm_vcpu *vcpu) +{ + unsigned long cpsr; + u32 cpsr_cond; + int cond; + + /* Top two bits non-zero? Unconditional. */ + if (kvm_vcpu_get_hsr(vcpu) >> 30) + return true; + + /* Is condition field valid? */ + cond = kvm_vcpu_get_condition(vcpu); + if (cond == 0xE) + return true; + + cpsr = *vcpu_cpsr(vcpu); + + if (cond < 0) { + /* This can happen in Thumb mode: examine IT state. */ + unsigned long it; + + it = ((cpsr >> 8) & 0xFC) | ((cpsr >> 25) & 0x3); + + /* it == 0 => unconditional. */ + if (it == 0) + return true; + + /* The cond for this insn works out as the top 4 bits. */ + cond = (it >> 4); + } + + cpsr_cond = cpsr >> 28; + + if (!((cc_map[cond] >> cpsr_cond) & 1)) + return false; + + return true; +} + +/** + * adjust_itstate - adjust ITSTATE when emulating instructions in IT-block + * @vcpu: The VCPU pointer + * + * When exceptions occur while instructions are executed in Thumb IF-THEN + * blocks, the ITSTATE field of the CPSR is not advanced (updated), so we have + * to do this little bit of work manually. The fields map like this: + * + * IT[7:0] -> CPSR[26:25],CPSR[15:10] + */ +static void kvm_adjust_itstate(struct kvm_vcpu *vcpu) +{ + unsigned long itbits, cond; + unsigned long cpsr = *vcpu_cpsr(vcpu); + bool is_arm = !(cpsr & COMPAT_PSR_T_BIT); + + if (is_arm || !(cpsr & COMPAT_PSR_IT_MASK)) + return; + + cond = (cpsr & 0xe000) >> 13; + itbits = (cpsr & 0x1c00) >> (10 - 2); + itbits |= (cpsr & (0x3 << 25)) >> 25; + + /* Perform ITAdvance (see page A2-52 in ARM DDI 0406C) */ + if ((itbits & 0x7) == 0) + itbits = cond = 0; + else + itbits = (itbits << 1) & 0x1f; + + cpsr &= ~COMPAT_PSR_IT_MASK; + cpsr |= cond << 13; + cpsr |= (itbits & 0x1c) << (10 - 2); + cpsr |= (itbits & 0x3) << 25; + *vcpu_cpsr(vcpu) = cpsr; +} + +/** + * kvm_skip_instr - skip a trapped instruction and proceed to the next + * @vcpu: The vcpu pointer + */ +void kvm_skip_instr32(struct kvm_vcpu *vcpu, bool is_wide_instr) +{ + bool is_thumb; + + is_thumb = !!(*vcpu_cpsr(vcpu) & COMPAT_PSR_T_BIT); + if (is_thumb && !is_wide_instr) + *vcpu_pc(vcpu) += 2; + else + *vcpu_pc(vcpu) += 4; + kvm_adjust_itstate(vcpu); +} -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
