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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2013-07-03 21:31:38 +0400 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-07-03 21:31:38 +0400 |
| commit | 1873e50028ce87dd9014049c86d71a898fa02166 (patch) | |
| tree | 046d37339278c3b88f0c248e9e6ff5fed804fe62 /arch/arm64/kvm/emulate.c | |
| parent | fb2af0020a51709ad87ea8055c325d3fbde04158 (diff) | |
| parent | aa729dccb5e8dfbc78e2e235b8754d6acccee731 (diff) | |
| download | linux-1873e50028ce87dd9014049c86d71a898fa02166.tar.xz | |
Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64
Pull ARM64 updates from Catalin Marinas:
"Main features:
- KVM and Xen ports to AArch64
- Hugetlbfs and transparent huge pages support for arm64
- Applied Micro X-Gene Kconfig entry and dts file
- Cache flushing improvements
For arm64 huge pages support, there are x86 changes moving part of
arch/x86/mm/hugetlbpage.c into mm/hugetlb.c to be re-used by arm64"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64: (66 commits)
arm64: Add initial DTS for APM X-Gene Storm SOC and APM Mustang board
arm64: Add defines for APM ARMv8 implementation
arm64: Enable APM X-Gene SOC family in the defconfig
arm64: Add Kconfig option for APM X-Gene SOC family
arm64/Makefile: provide vdso_install target
ARM64: mm: THP support.
ARM64: mm: Raise MAX_ORDER for 64KB pages and THP.
ARM64: mm: HugeTLB support.
ARM64: mm: Move PTE_PROT_NONE bit.
ARM64: mm: Make PAGE_NONE pages read only and no-execute.
ARM64: mm: Restore memblock limit when map_mem finished.
mm: thp: Correct the HPAGE_PMD_ORDER check.
x86: mm: Remove general hugetlb code from x86.
mm: hugetlb: Copy general hugetlb code from x86 to mm.
x86: mm: Remove x86 version of huge_pmd_share.
mm: hugetlb: Copy huge_pmd_share from x86 to mm.
arm64: KVM: document kernel object mappings in HYP
arm64: KVM: MAINTAINERS update
arm64: KVM: userspace API documentation
arm64: KVM: enable initialization of a 32bit vcpu
...
Diffstat (limited to 'arch/arm64/kvm/emulate.c')
| -rw-r--r-- | arch/arm64/kvm/emulate.c | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/arch/arm64/kvm/emulate.c b/arch/arm64/kvm/emulate.c new file mode 100644 index 000000000000..124418d17049 --- /dev/null +++ b/arch/arm64/kvm/emulate.c @@ -0,0 +1,158 @@ +/* + * (not much of an) Emulation layer for 32bit guests. + * + * Copyright (C) 2012,2013 - ARM Ltd + * Author: Marc Zyngier <marc.zyngier@arm.com> + * + * based on arch/arm/kvm/emulate.c + * Copyright (C) 2012 - Virtual Open Systems and Columbia University + * Author: Christoffer Dall <c.dall@virtualopensystems.com> + * + * 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 */ +}; + +static int kvm_vcpu_get_condition(const struct kvm_vcpu *vcpu) +{ + u32 esr = kvm_vcpu_get_hsr(vcpu); + + if (esr & ESR_EL2_CV) + return (esr & ESR_EL2_COND) >> ESR_EL2_COND_SHIFT; + + return -1; +} + +/* + * 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); +} |