guest.c

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// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2012,2013 - ARM Ltd
 * Author: Marc Zyngier <marc.zyngier@arm.com>
 *
 * Derived from arch/arm/kvm/guest.c:
 * Copyright (C) 2012 - Virtual Open Systems and Columbia University
 * Author: Christoffer Dall <c.dall@virtualopensystems.com>
 */
 
#include <linux/bits.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/nospec.h>
#include <linux/kvm_host.h>
#include <linux/module.h>
#include <linux/stddef.h>
#include <linux/string.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
#include <kvm/arm_hypercalls.h>
#include <asm/cputype.h>
#include <linux/uaccess.h>
#include <asm/fpsimd.h>
#include <asm/kvm.h>
#include <asm/kvm_emulate.h>
#include <asm/kvm_nested.h>
#include <asm/sigcontext.h>
 
#include "trace.h"
 
const struct _kvm_stats_desc kvm_vm_stats_desc[] = {
    KVM_GENERIC_VM_STATS()
};
 
const struct kvm_stats_header kvm_vm_stats_header = {
    .name_size = KVM_STATS_NAME_SIZE,
    .num_desc = ARRAY_SIZE(kvm_vm_stats_desc),
    .id_offset =  sizeof(struct kvm_stats_header),
    .desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE,
    .data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE +
               sizeof(kvm_vm_stats_desc),
};
 
const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = {
    KVM_GENERIC_VCPU_STATS(),
    STATS_DESC_COUNTER(VCPU, hvc_exit_stat),
    STATS_DESC_COUNTER(VCPU, wfe_exit_stat),
    STATS_DESC_COUNTER(VCPU, wfi_exit_stat),
    STATS_DESC_COUNTER(VCPU, mmio_exit_user),
    STATS_DESC_COUNTER(VCPU, mmio_exit_kernel),
    STATS_DESC_COUNTER(VCPU, signal_exits),
    STATS_DESC_COUNTER(VCPU, exits)
};
 
const struct kvm_stats_header kvm_vcpu_stats_header = {
    .name_size = KVM_STATS_NAME_SIZE,
    .num_desc = ARRAY_SIZE(kvm_vcpu_stats_desc),
    .id_offset = sizeof(struct kvm_stats_header),
    .desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE,
    .data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE +
               sizeof(kvm_vcpu_stats_desc),
};
 
static bool core_reg_offset_is_vreg(u64 off)
{
    return off >= KVM_REG_ARM_CORE_REG(fp_regs.vregs) &&
        off < KVM_REG_ARM_CORE_REG(fp_regs.fpsr);
}
 
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 core_reg_size_from_offset(const struct kvm_vcpu *vcpu, u64 off)
{
    int size;
 
    switch (off) {
    case KVM_REG_ARM_CORE_REG(regs.regs[0]) ...
         KVM_REG_ARM_CORE_REG(regs.regs[30]):
    case KVM_REG_ARM_CORE_REG(regs.sp):
    case KVM_REG_ARM_CORE_REG(regs.pc):
    case KVM_REG_ARM_CORE_REG(regs.pstate):
    case KVM_REG_ARM_CORE_REG(sp_el1):
    case KVM_REG_ARM_CORE_REG(elr_el1):
    case KVM_REG_ARM_CORE_REG(spsr[0]) ...
         KVM_REG_ARM_CORE_REG(spsr[KVM_NR_SPSR - 1]):
        size = sizeof(__u64);
        break;
 
    case KVM_REG_ARM_CORE_REG(fp_regs.vregs[0]) ...
         KVM_REG_ARM_CORE_REG(fp_regs.vregs[31]):
        size = sizeof(__uint128_t);
        break;
 
    case KVM_REG_ARM_CORE_REG(fp_regs.fpsr):
    case KVM_REG_ARM_CORE_REG(fp_regs.fpcr):
        size = sizeof(__u32);
        break;
 
    default:
        return -EINVAL;
    }
 
    if (!IS_ALIGNED(off, size / sizeof(__u32)))
        return -EINVAL;
 
    /*
     * The KVM_REG_ARM64_SVE regs must be used instead of
     * KVM_REG_ARM_CORE for accessing the FPSIMD V-registers on
     * SVE-enabled vcpus:
     */
    if (vcpu_has_sve(vcpu) && core_reg_offset_is_vreg(off))
        return -EINVAL;
 
    return size;
}
 
static void *core_reg_addr(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
    u64 off = core_reg_offset_from_id(reg->id);
    int size = core_reg_size_from_offset(vcpu, off);
 
    if (size < 0)
        return NULL;
 
    if (KVM_REG_SIZE(reg->id) != size)
        return NULL;
 
    switch (off) {
    case KVM_REG_ARM_CORE_REG(regs.regs[0]) ...
         KVM_REG_ARM_CORE_REG(regs.regs[30]):
        off -= KVM_REG_ARM_CORE_REG(regs.regs[0]);
        off /= 2;
        return &vcpu->arch.ctxt.regs.regs[off];
 
    case KVM_REG_ARM_CORE_REG(regs.sp):
        return &vcpu->arch.ctxt.regs.sp;
 
    case KVM_REG_ARM_CORE_REG(regs.pc):
        return &vcpu->arch.ctxt.regs.pc;
 
    case KVM_REG_ARM_CORE_REG(regs.pstate):
        return &vcpu->arch.ctxt.regs.pstate;
 
    case KVM_REG_ARM_CORE_REG(sp_el1):
        return __ctxt_sys_reg(&vcpu->arch.ctxt, SP_EL1);
 
    case KVM_REG_ARM_CORE_REG(elr_el1):
        return __ctxt_sys_reg(&vcpu->arch.ctxt, ELR_EL1);
 
    case KVM_REG_ARM_CORE_REG(spsr[KVM_SPSR_EL1]):
        return __ctxt_sys_reg(&vcpu->arch.ctxt, SPSR_EL1);
 
    case KVM_REG_ARM_CORE_REG(spsr[KVM_SPSR_ABT]):
        return &vcpu->arch.ctxt.spsr_abt;
 
    case KVM_REG_ARM_CORE_REG(spsr[KVM_SPSR_UND]):
        return &vcpu->arch.ctxt.spsr_und;
 
    case KVM_REG_ARM_CORE_REG(spsr[KVM_SPSR_IRQ]):
        return &vcpu->arch.ctxt.spsr_irq;
 
    case KVM_REG_ARM_CORE_REG(spsr[KVM_SPSR_FIQ]):
        return &vcpu->arch.ctxt.spsr_fiq;
 
    case KVM_REG_ARM_CORE_REG(fp_regs.vregs[0]) ...
         KVM_REG_ARM_CORE_REG(fp_regs.vregs[31]):
        off -= KVM_REG_ARM_CORE_REG(fp_regs.vregs[0]);
        off /= 4;
        return &vcpu->arch.ctxt.fp_regs.vregs[off];
 
    case KVM_REG_ARM_CORE_REG(fp_regs.fpsr):
        return &vcpu->arch.ctxt.fp_regs.fpsr;
 
    case KVM_REG_ARM_CORE_REG(fp_regs.fpcr):
        return &vcpu->arch.ctxt.fp_regs.fpcr;
 
    default:
        return NULL;
    }
}
 
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;
    int nr_regs = sizeof(struct kvm_regs) / sizeof(__u32);
    void *addr;
    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;
 
    addr = core_reg_addr(vcpu, reg);
    if (!addr)
        return -EINVAL;
 
    if (copy_to_user(uaddr, addr, 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;
    int nr_regs = sizeof(struct kvm_regs) / sizeof(__u32);
    __uint128_t tmp;
    void *valp = &tmp, *addr;
    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;
 
    addr = core_reg_addr(vcpu, reg);
    if (!addr)
        return -EINVAL;
 
    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)) {
        u64 mode = (*(u64 *)valp) & PSR_AA32_MODE_MASK;
        switch (mode) {
        case PSR_AA32_MODE_USR:
            if (!kvm_supports_32bit_el0())
                return -EINVAL;
            break;
        case PSR_AA32_MODE_FIQ:
        case PSR_AA32_MODE_IRQ:
        case PSR_AA32_MODE_SVC:
        case PSR_AA32_MODE_ABT:
        case PSR_AA32_MODE_UND:
            if (!vcpu_el1_is_32bit(vcpu))
                return -EINVAL;
            break;
        case PSR_MODE_EL2h:
        case PSR_MODE_EL2t:
            if (!vcpu_has_nv(vcpu))
                return -EINVAL;
            fallthrough;
        case PSR_MODE_EL0t:
        case PSR_MODE_EL1t:
        case PSR_MODE_EL1h:
            if (vcpu_el1_is_32bit(vcpu))
                return -EINVAL;
            break;
        default:
            err = -EINVAL;
            goto out;
        }
    }
 
    memcpy(addr, valp, KVM_REG_SIZE(reg->id));
 
    if (*vcpu_cpsr(vcpu) & PSR_MODE32_BIT) {
        int i, nr_reg;
 
        switch (*vcpu_cpsr(vcpu)) {
        /*
         * Either we are dealing with user mode, and only the
         * first 15 registers (+ PC) must be narrowed to 32bit.
         * AArch32 r0-r14 conveniently map to AArch64 x0-x14.
         */
        case PSR_AA32_MODE_USR:
        case PSR_AA32_MODE_SYS:
            nr_reg = 15;
            break;
 
        /*
         * Otherwise, this is a privileged mode, and *all* the
         * registers must be narrowed to 32bit.
         */
        default:
            nr_reg = 31;
            break;
        }
 
        for (i = 0; i < nr_reg; i++)
            vcpu_set_reg(vcpu, i, (u32)vcpu_get_reg(vcpu, i));
 
        *vcpu_pc(vcpu) = (u32)*vcpu_pc(vcpu);
    }
out:
    return err;
}
 
#define vq_word(vq) (((vq) - SVE_VQ_MIN) / 64)
#define vq_mask(vq) ((u64)1 << ((vq) - SVE_VQ_MIN) % 64)
#define vq_present(vqs, vq) (!!((vqs)[vq_word(vq)] & vq_mask(vq)))
 
static int get_sve_vls(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
    unsigned int max_vq, vq;
    u64 vqs[KVM_ARM64_SVE_VLS_WORDS];
 
    if (!vcpu_has_sve(vcpu))
        return -ENOENT;
 
    if (WARN_ON(!sve_vl_valid(vcpu->arch.sve_max_vl)))
        return -EINVAL;
 
    memset(vqs, 0, sizeof(vqs));
 
    max_vq = vcpu_sve_max_vq(vcpu);
    for (vq = SVE_VQ_MIN; vq <= max_vq; ++vq)
        if (sve_vq_available(vq))
            vqs[vq_word(vq)] |= vq_mask(vq);
 
    if (copy_to_user((void __user *)reg->addr, vqs, sizeof(vqs)))
        return -EFAULT;
 
    return 0;
}
 
static int set_sve_vls(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
    unsigned int max_vq, vq;
    u64 vqs[KVM_ARM64_SVE_VLS_WORDS];
 
    if (!vcpu_has_sve(vcpu))
        return -ENOENT;
 
    if (kvm_arm_vcpu_sve_finalized(vcpu))
        return -EPERM; /* too late! */
 
    if (WARN_ON(vcpu->arch.sve_state))
        return -EINVAL;
 
    if (copy_from_user(vqs, (const void __user *)reg->addr, sizeof(vqs)))
        return -EFAULT;
 
    max_vq = 0;
    for (vq = SVE_VQ_MIN; vq <= SVE_VQ_MAX; ++vq)
        if (vq_present(vqs, vq))
            max_vq = vq;
 
    if (max_vq > sve_vq_from_vl(kvm_sve_max_vl))
        return -EINVAL;
 
    /*
     * Vector lengths supported by the host can't currently be
     * hidden from the guest individually: instead we can only set a
     * maximum via ZCR_EL2.LEN.  So, make sure the available vector
     * lengths match the set requested exactly up to the requested
     * maximum:
     */
    for (vq = SVE_VQ_MIN; vq <= max_vq; ++vq)
        if (vq_present(vqs, vq) != sve_vq_available(vq))
            return -EINVAL;
 
    /* Can't run with no vector lengths at all: */
    if (max_vq < SVE_VQ_MIN)
        return -EINVAL;
 
    /* vcpu->arch.sve_state will be alloc'd by kvm_vcpu_finalize_sve() */
    vcpu->arch.sve_max_vl = sve_vl_from_vq(max_vq);
 
    return 0;
}
 
#define SVE_REG_SLICE_SHIFT 0
#define SVE_REG_SLICE_BITS  5
#define SVE_REG_ID_SHIFT    (SVE_REG_SLICE_SHIFT + SVE_REG_SLICE_BITS)
#define SVE_REG_ID_BITS     5
 
#define SVE_REG_SLICE_MASK                  \
    GENMASK(SVE_REG_SLICE_SHIFT + SVE_REG_SLICE_BITS - 1,   \
        SVE_REG_SLICE_SHIFT)
#define SVE_REG_ID_MASK                         \
    GENMASK(SVE_REG_ID_SHIFT + SVE_REG_ID_BITS - 1, SVE_REG_ID_SHIFT)
 
#define SVE_NUM_SLICES (1 << SVE_REG_SLICE_BITS)
 
#define KVM_SVE_ZREG_SIZE KVM_REG_SIZE(KVM_REG_ARM64_SVE_ZREG(0, 0))
#define KVM_SVE_PREG_SIZE KVM_REG_SIZE(KVM_REG_ARM64_SVE_PREG(0, 0))
 
/*
 * Number of register slices required to cover each whole SVE register.
 * NOTE: Only the first slice every exists, for now.
 * If you are tempted to modify this, you must also rework sve_reg_to_region()
 * to match:
 */
#define vcpu_sve_slices(vcpu) 1
 
/* Bounds of a single SVE register slice within vcpu->arch.sve_state */
struct sve_state_reg_region {
    unsigned int koffset;   /* offset into sve_state in kernel memory */
    unsigned int klen;  /* length in kernel memory */
    unsigned int upad;  /* extra trailing padding in user memory */
};
 
/*
 * Validate SVE register ID and get sanitised bounds for user/kernel SVE
 * register copy
 */
static int sve_reg_to_region(struct sve_state_reg_region *region,
                 struct kvm_vcpu *vcpu,
                 const struct kvm_one_reg *reg)
{
    /* reg ID ranges for Z- registers */
    const u64 zreg_id_min = KVM_REG_ARM64_SVE_ZREG(0, 0);
    const u64 zreg_id_max = KVM_REG_ARM64_SVE_ZREG(SVE_NUM_ZREGS - 1,
                               SVE_NUM_SLICES - 1);
 
    /* reg ID ranges for P- registers and FFR (which are contiguous) */
    const u64 preg_id_min = KVM_REG_ARM64_SVE_PREG(0, 0);
    const u64 preg_id_max = KVM_REG_ARM64_SVE_FFR(SVE_NUM_SLICES - 1);
 
    unsigned int vq;
    unsigned int reg_num;
 
    unsigned int reqoffset, reqlen; /* User-requested offset and length */
    unsigned int maxlen; /* Maximum permitted length */
 
    size_t sve_state_size;
 
    const u64 last_preg_id = KVM_REG_ARM64_SVE_PREG(SVE_NUM_PREGS - 1,
                            SVE_NUM_SLICES - 1);
 
    /* Verify that the P-regs and FFR really do have contiguous IDs: */
    BUILD_BUG_ON(KVM_REG_ARM64_SVE_FFR(0) != last_preg_id + 1);
 
    /* Verify that we match the UAPI header: */
    BUILD_BUG_ON(SVE_NUM_SLICES != KVM_ARM64_SVE_MAX_SLICES);
 
    reg_num = (reg->id & SVE_REG_ID_MASK) >> SVE_REG_ID_SHIFT;
 
    if (reg->id >= zreg_id_min && reg->id <= zreg_id_max) {
        if (!vcpu_has_sve(vcpu) || (reg->id & SVE_REG_SLICE_MASK) > 0)
            return -ENOENT;
 
        vq = vcpu_sve_max_vq(vcpu);
 
        reqoffset = SVE_SIG_ZREG_OFFSET(vq, reg_num) -
                SVE_SIG_REGS_OFFSET;
        reqlen = KVM_SVE_ZREG_SIZE;
        maxlen = SVE_SIG_ZREG_SIZE(vq);
    } else if (reg->id >= preg_id_min && reg->id <= preg_id_max) {
        if (!vcpu_has_sve(vcpu) || (reg->id & SVE_REG_SLICE_MASK) > 0)
            return -ENOENT;
 
        vq = vcpu_sve_max_vq(vcpu);
 
        reqoffset = SVE_SIG_PREG_OFFSET(vq, reg_num) -
                SVE_SIG_REGS_OFFSET;
        reqlen = KVM_SVE_PREG_SIZE;
        maxlen = SVE_SIG_PREG_SIZE(vq);
    } else {
        return -EINVAL;
    }
 
    sve_state_size = vcpu_sve_state_size(vcpu);
    if (WARN_ON(!sve_state_size))
        return -EINVAL;
 
    region->koffset = array_index_nospec(reqoffset, sve_state_size);
    region->klen = min(maxlen, reqlen);
    region->upad = reqlen - region->klen;
 
    return 0;
}
 
static int get_sve_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
    int ret;
    struct sve_state_reg_region region;
    char __user *uptr = (char __user *)reg->addr;
 
    /* Handle the KVM_REG_ARM64_SVE_VLS pseudo-reg as a special case: */
    if (reg->id == KVM_REG_ARM64_SVE_VLS)
        return get_sve_vls(vcpu, reg);
 
    /* Try to interpret reg ID as an architectural SVE register... */
    ret = sve_reg_to_region(&region, vcpu, reg);
    if (ret)
        return ret;
 
    if (!kvm_arm_vcpu_sve_finalized(vcpu))
        return -EPERM;
 
    if (copy_to_user(uptr, vcpu->arch.sve_state + region.koffset,
             region.klen) ||
        clear_user(uptr + region.klen, region.upad))
        return -EFAULT;
 
    return 0;
}
 
static int set_sve_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
    int ret;
    struct sve_state_reg_region region;
    const char __user *uptr = (const char __user *)reg->addr;
 
    /* Handle the KVM_REG_ARM64_SVE_VLS pseudo-reg as a special case: */
    if (reg->id == KVM_REG_ARM64_SVE_VLS)
        return set_sve_vls(vcpu, reg);
 
    /* Try to interpret reg ID as an architectural SVE register... */
    ret = sve_reg_to_region(&region, vcpu, reg);
    if (ret)
        return ret;
 
    if (!kvm_arm_vcpu_sve_finalized(vcpu))
        return -EPERM;
 
    if (copy_from_user(vcpu->arch.sve_state + region.koffset, uptr,
               region.klen))
        return -EFAULT;
 
    return 0;
}
 
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 int copy_core_reg_indices(const struct kvm_vcpu *vcpu,
                 u64 __user *uindices)
{
    unsigned int i;
    int n = 0;
 
    for (i = 0; i < sizeof(struct kvm_regs) / sizeof(__u32); i++) {
        u64 reg = KVM_REG_ARM64 | KVM_REG_ARM_CORE | i;
        int size = core_reg_size_from_offset(vcpu, i);
 
        if (size < 0)
            continue;
 
        switch (size) {
        case sizeof(__u32):
            reg |= KVM_REG_SIZE_U32;
            break;
 
        case sizeof(__u64):
            reg |= KVM_REG_SIZE_U64;
            break;
 
        case sizeof(__uint128_t):
            reg |= KVM_REG_SIZE_U128;
            break;
 
        default:
            WARN_ON(1);
            continue;
        }
 
        if (uindices) {
            if (put_user(reg, uindices))
                return -EFAULT;
            uindices++;
        }
 
        n++;
    }
 
    return n;
}
 
static unsigned long num_core_regs(const struct kvm_vcpu *vcpu)
{
    return copy_core_reg_indices(vcpu, NULL);
}
 
static const u64 timer_reg_list[] = {
    KVM_REG_ARM_TIMER_CTL,
    KVM_REG_ARM_TIMER_CNT,
    KVM_REG_ARM_TIMER_CVAL,
    KVM_REG_ARM_PTIMER_CTL,
    KVM_REG_ARM_PTIMER_CNT,
    KVM_REG_ARM_PTIMER_CVAL,
};
 
#define NUM_TIMER_REGS ARRAY_SIZE(timer_reg_list)
 
static bool is_timer_reg(u64 index)
{
    switch (index) {
    case KVM_REG_ARM_TIMER_CTL:
    case KVM_REG_ARM_TIMER_CNT:
    case KVM_REG_ARM_TIMER_CVAL:
    case KVM_REG_ARM_PTIMER_CTL:
    case KVM_REG_ARM_PTIMER_CNT:
    case KVM_REG_ARM_PTIMER_CVAL:
        return true;
    }
    return false;
}
 
static int copy_timer_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
{
    for (int i = 0; i < NUM_TIMER_REGS; i++) {
        if (put_user(timer_reg_list[i], uindices))
            return -EFAULT;
        uindices++;
    }
 
    return 0;
}
 
static int set_timer_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
    void __user *uaddr = (void __user *)(long)reg->addr;
    u64 val;
    int ret;
 
    ret = copy_from_user(&val, uaddr, KVM_REG_SIZE(reg->id));
    if (ret != 0)
        return -EFAULT;
 
    return kvm_arm_timer_set_reg(vcpu, reg->id, val);
}
 
static int get_timer_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
    void __user *uaddr = (void __user *)(long)reg->addr;
    u64 val;
 
    val = kvm_arm_timer_get_reg(vcpu, reg->id);
    return copy_to_user(uaddr, &val, KVM_REG_SIZE(reg->id)) ? -EFAULT : 0;
}
 
static unsigned long num_sve_regs(const struct kvm_vcpu *vcpu)
{
    const unsigned int slices = vcpu_sve_slices(vcpu);
 
    if (!vcpu_has_sve(vcpu))
        return 0;
 
    /* Policed by KVM_GET_REG_LIST: */
    WARN_ON(!kvm_arm_vcpu_sve_finalized(vcpu));
 
    return slices * (SVE_NUM_PREGS + SVE_NUM_ZREGS + 1 /* FFR */)
        + 1; /* KVM_REG_ARM64_SVE_VLS */
}
 
static int copy_sve_reg_indices(const struct kvm_vcpu *vcpu,
                u64 __user *uindices)
{
    const unsigned int slices = vcpu_sve_slices(vcpu);
    u64 reg;
    unsigned int i, n;
    int num_regs = 0;
 
    if (!vcpu_has_sve(vcpu))
        return 0;
 
    /* Policed by KVM_GET_REG_LIST: */
    WARN_ON(!kvm_arm_vcpu_sve_finalized(vcpu));
 
    /*
     * Enumerate this first, so that userspace can save/restore in
     * the order reported by KVM_GET_REG_LIST:
     */
    reg = KVM_REG_ARM64_SVE_VLS;
    if (put_user(reg, uindices++))
        return -EFAULT;
    ++num_regs;
 
    for (i = 0; i < slices; i++) {
        for (n = 0; n < SVE_NUM_ZREGS; n++) {
            reg = KVM_REG_ARM64_SVE_ZREG(n, i);
            if (put_user(reg, uindices++))
                return -EFAULT;
            num_regs++;
        }
 
        for (n = 0; n < SVE_NUM_PREGS; n++) {
            reg = KVM_REG_ARM64_SVE_PREG(n, i);
            if (put_user(reg, uindices++))
                return -EFAULT;
            num_regs++;
        }
 
        reg = KVM_REG_ARM64_SVE_FFR(i);
        if (put_user(reg, uindices++))
            return -EFAULT;
        num_regs++;
    }
 
    return num_regs;
}
 
/**
 * 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)
{
    unsigned long res = 0;
 
    res += num_core_regs(vcpu);
    res += num_sve_regs(vcpu);
    res += kvm_arm_num_sys_reg_descs(vcpu);
    res += kvm_arm_get_fw_num_regs(vcpu);
    res += NUM_TIMER_REGS;
 
    return res;
}
 
/**
 * kvm_arm_copy_reg_indices - get indices of all registers.
 *
 * We do core registers right here, then we append system regs.
 */
int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
{
    int ret;
 
    ret = copy_core_reg_indices(vcpu, uindices);
    if (ret < 0)
        return ret;
    uindices += ret;
 
    ret = copy_sve_reg_indices(vcpu, uindices);
    if (ret < 0)
        return ret;
    uindices += ret;
 
    ret = kvm_arm_copy_fw_reg_indices(vcpu, uindices);
    if (ret < 0)
        return ret;
    uindices += kvm_arm_get_fw_num_regs(vcpu);
 
    ret = copy_timer_indices(vcpu, uindices);
    if (ret < 0)
        return ret;
    uindices += NUM_TIMER_REGS;
 
    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;
 
    switch (reg->id & KVM_REG_ARM_COPROC_MASK) {
    case KVM_REG_ARM_CORE:  return get_core_reg(vcpu, reg);
    case KVM_REG_ARM_FW:
    case KVM_REG_ARM_FW_FEAT_BMAP:
        return kvm_arm_get_fw_reg(vcpu, reg);
    case KVM_REG_ARM64_SVE: return get_sve_reg(vcpu, reg);
    }
 
    if (is_timer_reg(reg->id))
        return get_timer_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;
 
    switch (reg->id & KVM_REG_ARM_COPROC_MASK) {
    case KVM_REG_ARM_CORE:  return set_core_reg(vcpu, reg);
    case KVM_REG_ARM_FW:
    case KVM_REG_ARM_FW_FEAT_BMAP:
        return kvm_arm_set_fw_reg(vcpu, reg);
    case KVM_REG_ARM64_SVE: return set_sve_reg(vcpu, reg);
    }
 
    if (is_timer_reg(reg->id))
        return set_timer_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 __kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
                  struct kvm_vcpu_events *events)
{
    events->exception.serror_pending = !!(vcpu->arch.hcr_el2 & HCR_VSE);
    events->exception.serror_has_esr = cpus_have_final_cap(ARM64_HAS_RAS_EXTN);
 
    if (events->exception.serror_pending && events->exception.serror_has_esr)
        events->exception.serror_esr = vcpu_get_vsesr(vcpu);
 
    /*
     * We never return a pending ext_dabt here because we deliver it to
     * the virtual CPU directly when setting the event and it's no longer
     * 'pending' at this point.
     */
 
    return 0;
}
 
int __kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
                  struct kvm_vcpu_events *events)
{
    bool serror_pending = events->exception.serror_pending;
    bool has_esr = events->exception.serror_has_esr;
    bool ext_dabt_pending = events->exception.ext_dabt_pending;
 
    if (serror_pending && has_esr) {
        if (!cpus_have_final_cap(ARM64_HAS_RAS_EXTN))
            return -EINVAL;
 
        if (!((events->exception.serror_esr) & ~ESR_ELx_ISS_MASK))
            kvm_set_sei_esr(vcpu, events->exception.serror_esr);
        else
            return -EINVAL;
    } else if (serror_pending) {
        kvm_inject_vabt(vcpu);
    }
 
    if (ext_dabt_pending)
        kvm_inject_dabt(vcpu, kvm_vcpu_get_hfar(vcpu));
 
    return 0;
}
 
u32 __attribute_const__ kvm_target_cpu(void)
{
    unsigned long implementor = read_cpuid_implementor();
    unsigned long part_number = read_cpuid_part_number();
 
    switch (implementor) {
    case ARM_CPU_IMP_ARM:
        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_A53:
            return KVM_ARM_TARGET_CORTEX_A53;
        case ARM_CPU_PART_CORTEX_A57:
            return KVM_ARM_TARGET_CORTEX_A57;
        }
        break;
    case ARM_CPU_IMP_APM:
        switch (part_number) {
        case APM_CPU_PART_XGENE:
            return KVM_ARM_TARGET_XGENE_POTENZA;
        }
        break;
    }
 
    /* Return a default generic target */
    return KVM_ARM_TARGET_GENERIC_V8;
}
 
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;
}
 
/**
 * kvm_arch_vcpu_ioctl_set_guest_debug - set up guest debugging
 * @kvm:    pointer to the KVM struct
 * @kvm_guest_debug: the ioctl data buffer
 *
 * This sets up and enables the VM for guest debugging. Userspace
 * passes in a control flag to enable different debug types and
 * potentially other architecture specific information in the rest of
 * the structure.
 */
int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
                    struct kvm_guest_debug *dbg)
{
    int ret = 0;
 
    trace_kvm_set_guest_debug(vcpu, dbg->control);
 
    if (dbg->control & ~KVM_GUESTDBG_VALID_MASK) {
        ret = -EINVAL;
        goto out;
    }
 
    if (dbg->control & KVM_GUESTDBG_ENABLE) {
        vcpu->guest_debug = dbg->control;
 
        /* Hardware assisted Break and Watch points */
        if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW) {
            vcpu->arch.external_debug_state = dbg->arch;
        }
 
    } else {
        /* If not enabled clear all flags */
        vcpu->guest_debug = 0;
        vcpu_clear_flag(vcpu, DBG_SS_ACTIVE_PENDING);
    }
 
out:
    return ret;
}
 
int kvm_arm_vcpu_arch_set_attr(struct kvm_vcpu *vcpu,
                   struct kvm_device_attr *attr)
{
    int ret;
 
    switch (attr->group) {
    case KVM_ARM_VCPU_PMU_V3_CTRL:
        mutex_lock(&vcpu->kvm->arch.config_lock);
        ret = kvm_arm_pmu_v3_set_attr(vcpu, attr);
        mutex_unlock(&vcpu->kvm->arch.config_lock);
        break;
    case KVM_ARM_VCPU_TIMER_CTRL:
        ret = kvm_arm_timer_set_attr(vcpu, attr);
        break;
    case KVM_ARM_VCPU_PVTIME_CTRL:
        ret = kvm_arm_pvtime_set_attr(vcpu, attr);
        break;
    default:
        ret = -ENXIO;
        break;
    }
 
    return ret;
}
 
int kvm_arm_vcpu_arch_get_attr(struct kvm_vcpu *vcpu,
                   struct kvm_device_attr *attr)
{
    int ret;
 
    switch (attr->group) {
    case KVM_ARM_VCPU_PMU_V3_CTRL:
        ret = kvm_arm_pmu_v3_get_attr(vcpu, attr);
        break;
    case KVM_ARM_VCPU_TIMER_CTRL:
        ret = kvm_arm_timer_get_attr(vcpu, attr);
        break;
    case KVM_ARM_VCPU_PVTIME_CTRL:
        ret = kvm_arm_pvtime_get_attr(vcpu, attr);
        break;
    default:
        ret = -ENXIO;
        break;
    }
 
    return ret;
}
 
int kvm_arm_vcpu_arch_has_attr(struct kvm_vcpu *vcpu,
                   struct kvm_device_attr *attr)
{
    int ret;
 
    switch (attr->group) {
    case KVM_ARM_VCPU_PMU_V3_CTRL:
        ret = kvm_arm_pmu_v3_has_attr(vcpu, attr);
        break;
    case KVM_ARM_VCPU_TIMER_CTRL:
        ret = kvm_arm_timer_has_attr(vcpu, attr);
        break;
    case KVM_ARM_VCPU_PVTIME_CTRL:
        ret = kvm_arm_pvtime_has_attr(vcpu, attr);
        break;
    default:
        ret = -ENXIO;
        break;
    }
 
    return ret;
}
 
int kvm_vm_ioctl_mte_copy_tags(struct kvm *kvm,
                   struct kvm_arm_copy_mte_tags *copy_tags)
{
    gpa_t guest_ipa = copy_tags->guest_ipa;
    size_t length = copy_tags->length;
    void __user *tags = copy_tags->addr;
    gpa_t gfn;
    bool write = !(copy_tags->flags & KVM_ARM_TAGS_FROM_GUEST);
    int ret = 0;
 
    if (!kvm_has_mte(kvm))
        return -EINVAL;
 
    if (copy_tags->reserved[0] || copy_tags->reserved[1])
        return -EINVAL;
 
    if (copy_tags->flags & ~KVM_ARM_TAGS_FROM_GUEST)
        return -EINVAL;
 
    if (length & ~PAGE_MASK || guest_ipa & ~PAGE_MASK)
        return -EINVAL;
 
    /* Lengths above INT_MAX cannot be represented in the return value */
    if (length > INT_MAX)
        return -EINVAL;
 
    gfn = gpa_to_gfn(guest_ipa);
 
    mutex_lock(&kvm->slots_lock);
 
    while (length > 0) {
        kvm_pfn_t pfn = gfn_to_pfn_prot(kvm, gfn, write, NULL);
        void *maddr;
        unsigned long num_tags;
        struct page *page;
 
        if (is_error_noslot_pfn(pfn)) {
            ret = -EFAULT;
            goto out;
        }
 
        page = pfn_to_online_page(pfn);
        if (!page) {
            /* Reject ZONE_DEVICE memory */
            ret = -EFAULT;
            goto out;
        }
        maddr = page_address(page);
 
        if (!write) {
            if (page_mte_tagged(page))
                num_tags = mte_copy_tags_to_user(tags, maddr,
                            MTE_GRANULES_PER_PAGE);
            else
                /* No tags in memory, so write zeros */
                num_tags = MTE_GRANULES_PER_PAGE -
                    clear_user(tags, MTE_GRANULES_PER_PAGE);
            kvm_release_pfn_clean(pfn);
        } else {
            /*
             * Only locking to serialise with a concurrent
             * set_pte_at() in the VMM but still overriding the
             * tags, hence ignoring the return value.
             */
            try_page_mte_tagging(page);
            num_tags = mte_copy_tags_from_user(maddr, tags,
                            MTE_GRANULES_PER_PAGE);
 
            /* uaccess failed, don't leave stale tags */
            if (num_tags != MTE_GRANULES_PER_PAGE)
                mte_clear_page_tags(maddr);
            set_page_mte_tagged(page);
 
            kvm_release_pfn_dirty(pfn);
        }
 
        if (num_tags != MTE_GRANULES_PER_PAGE) {
            ret = -EFAULT;
            goto out;
        }
 
        gfn++;
        tags += num_tags;
        length -= PAGE_SIZE;
    }
 
out:
    mutex_unlock(&kvm->slots_lock);
    /* If some data has been copied report the number of bytes copied */
    if (length != copy_tags->length)
        return copy_tags->length - length;
    return ret;
}