From 2f4a07c5f9fe4a5cdb9867e1e2fcab3165846ea7 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Mon, 10 Dec 2012 16:37:02 +0000 Subject: [PATCH] arm64: KVM: guest one-reg interface Let userspace play with the guest registers. Reviewed-by: Christopher Covington Signed-off-by: Marc Zyngier --- arch/arm64/kvm/guest.c | 259 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 259 insertions(+) create mode 100644 arch/arm64/kvm/guest.c diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c new file mode 100644 index 000000000000..3d7518a7ebaa --- /dev/null +++ b/arch/arm64/kvm/guest.c @@ -0,0 +1,259 @@ +/* + * Copyright (C) 2012,2013 - ARM Ltd + * Author: Marc Zyngier + * + * Derived from arch/arm/kvm/guest.c: + * Copyright (C) 2012 - Virtual Open Systems and Columbia University + * Author: Christoffer Dall + * + * 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 . + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +struct kvm_stats_debugfs_item debugfs_entries[] = { + { NULL } +}; + +int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu) +{ + vcpu->arch.hcr_el2 = HCR_GUEST_FLAGS; + return 0; +} + +static u64 core_reg_offset_from_id(u64 id) +{ + return id & ~(KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK | KVM_REG_ARM_CORE); +} + +static int get_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) +{ + /* + * Because the kvm_regs structure is a mix of 32, 64 and + * 128bit fields, we index it as if it was a 32bit + * array. Hence below, nr_regs is the number of entries, and + * off the index in the "array". + */ + __u32 __user *uaddr = (__u32 __user *)(unsigned long)reg->addr; + struct kvm_regs *regs = vcpu_gp_regs(vcpu); + int nr_regs = sizeof(*regs) / sizeof(__u32); + u32 off; + + /* Our ID is an index into the kvm_regs struct. */ + off = core_reg_offset_from_id(reg->id); + if (off >= nr_regs || + (off + (KVM_REG_SIZE(reg->id) / sizeof(__u32))) >= nr_regs) + return -ENOENT; + + if (copy_to_user(uaddr, ((u32 *)regs) + off, KVM_REG_SIZE(reg->id))) + return -EFAULT; + + return 0; +} + +static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) +{ + __u32 __user *uaddr = (__u32 __user *)(unsigned long)reg->addr; + struct kvm_regs *regs = vcpu_gp_regs(vcpu); + int nr_regs = sizeof(*regs) / sizeof(__u32); + __uint128_t tmp; + void *valp = &tmp; + u64 off; + int err = 0; + + /* Our ID is an index into the kvm_regs struct. */ + off = core_reg_offset_from_id(reg->id); + if (off >= nr_regs || + (off + (KVM_REG_SIZE(reg->id) / sizeof(__u32))) >= nr_regs) + return -ENOENT; + + if (KVM_REG_SIZE(reg->id) > sizeof(tmp)) + return -EINVAL; + + if (copy_from_user(valp, uaddr, KVM_REG_SIZE(reg->id))) { + err = -EFAULT; + goto out; + } + + if (off == KVM_REG_ARM_CORE_REG(regs.pstate)) { + u32 mode = (*(u32 *)valp) & COMPAT_PSR_MODE_MASK; + switch (mode) { + case PSR_MODE_EL0t: + case PSR_MODE_EL1t: + case PSR_MODE_EL1h: + break; + default: + err = -EINVAL; + goto out; + } + } + + memcpy((u32 *)regs + off, valp, KVM_REG_SIZE(reg->id)); +out: + return err; +} + +int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs) +{ + return -EINVAL; +} + +int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs) +{ + return -EINVAL; +} + +static unsigned long num_core_regs(void) +{ + return sizeof(struct kvm_regs) / sizeof(__u32); +} + +/** + * kvm_arm_num_regs - how many registers do we present via KVM_GET_ONE_REG + * + * This is for all registers. + */ +unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu) +{ + return num_core_regs() + kvm_arm_num_sys_reg_descs(vcpu); +} + +/** + * kvm_arm_copy_reg_indices - get indices of all registers. + * + * We do core registers right here, then we apppend system regs. + */ +int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices) +{ + unsigned int i; + const u64 core_reg = KVM_REG_ARM64 | KVM_REG_SIZE_U64 | KVM_REG_ARM_CORE; + + for (i = 0; i < sizeof(struct kvm_regs) / sizeof(__u32); i++) { + if (put_user(core_reg | i, uindices)) + return -EFAULT; + uindices++; + } + + return kvm_arm_copy_sys_reg_indices(vcpu, uindices); +} + +int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) +{ + /* We currently use nothing arch-specific in upper 32 bits */ + if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM64 >> 32) + return -EINVAL; + + /* Register group 16 means we want a core register. */ + if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE) + return get_core_reg(vcpu, reg); + + return kvm_arm_sys_reg_get_reg(vcpu, reg); +} + +int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) +{ + /* We currently use nothing arch-specific in upper 32 bits */ + if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM64 >> 32) + return -EINVAL; + + /* Register group 16 means we set a core register. */ + if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE) + return set_core_reg(vcpu, reg); + + return kvm_arm_sys_reg_set_reg(vcpu, reg); +} + +int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu, + struct kvm_sregs *sregs) +{ + return -EINVAL; +} + +int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu, + struct kvm_sregs *sregs) +{ + return -EINVAL; +} + +int __attribute_const__ kvm_target_cpu(void) +{ + unsigned long implementor = read_cpuid_implementor(); + unsigned long part_number = read_cpuid_part_number(); + + if (implementor != ARM_CPU_IMP_ARM) + return -EINVAL; + + switch (part_number) { + case ARM_CPU_PART_AEM_V8: + return KVM_ARM_TARGET_AEM_V8; + case ARM_CPU_PART_FOUNDATION: + return KVM_ARM_TARGET_FOUNDATION_V8; + case ARM_CPU_PART_CORTEX_A57: + /* Currently handled by the generic backend */ + return KVM_ARM_TARGET_CORTEX_A57; + default: + return -EINVAL; + } +} + +int kvm_vcpu_set_target(struct kvm_vcpu *vcpu, + const struct kvm_vcpu_init *init) +{ + unsigned int i; + int phys_target = kvm_target_cpu(); + + if (init->target != phys_target) + return -EINVAL; + + vcpu->arch.target = phys_target; + bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES); + + /* -ENOENT for unknown features, -EINVAL for invalid combinations. */ + for (i = 0; i < sizeof(init->features) * 8; i++) { + if (init->features[i / 32] & (1 << (i % 32))) { + if (i >= KVM_VCPU_MAX_FEATURES) + return -ENOENT; + set_bit(i, vcpu->arch.features); + } + } + + /* Now we know what it is, we can reset it. */ + return kvm_reset_vcpu(vcpu); +} + +int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu) +{ + return -EINVAL; +} + +int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu) +{ + return -EINVAL; +} + +int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu, + struct kvm_translation *tr) +{ + return -EINVAL; +} -- GitLab