path: root/target-ppc/kvm.c

/*
 * PowerPC implementation of KVM hooks
 *
 * Copyright IBM Corp. 2007
 * Copyright (C) 2011 Freescale Semiconductor, Inc.
 *
 * Authors:
 *  Jerone Young <jyoung5@us.ibm.com>
 *  Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
 *  Hollis Blanchard <hollisb@us.ibm.com>
 *
 * This work is licensed under the terms of the GNU GPL, version 2 or later.
 * See the COPYING file in the top-level directory.
 *
 */

#include <dirent.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/vfs.h>

#include <linux/kvm.h>

#include "qemu-common.h"
#include "qemu/timer.h"
#include "sysemu/sysemu.h"
#include "sysemu/kvm.h"
#include "kvm_ppc.h"
#include "cpu.h"
#include "sysemu/cpus.h"
#include "sysemu/device_tree.h"
#include "hw/sysbus.h"
#include "hw/spapr.h"

#include "hw/sysbus.h"
#include "hw/spapr.h"
#include "hw/spapr_vio.h"

//#define DEBUG_KVM

#ifdef DEBUG_KVM
#define dprintf(fmt, ...) \
    do { fprintf(stderr, fmt, ## __VA_ARGS__); } while (0)
#else
#define dprintf(fmt, ...) \
    do { } while (0)
#endif

#define PROC_DEVTREE_CPU      "/proc/device-tree/cpus/"

const KVMCapabilityInfo kvm_arch_required_capabilities[] = {
    KVM_CAP_LAST_INFO
};

static int cap_interrupt_unset = false;
static int cap_interrupt_level = false;
static int cap_segstate;
static int cap_booke_sregs;
static int cap_ppc_smt;
static int cap_ppc_rma;
static int cap_spapr_tce;
static int cap_hior;
static int cap_one_reg;

/* XXX We have a race condition where we actually have a level triggered
 *     interrupt, but the infrastructure can't expose that yet, so the guest
 *     takes but ignores it, goes to sleep and never gets notified that there's
 *     still an interrupt pending.
 *
 *     As a quick workaround, let's just wake up again 20 ms after we injected
 *     an interrupt. That way we can assure that we're always reinjecting
 *     interrupts in case the guest swallowed them.
 */
static QEMUTimer *idle_timer;

static void kvm_kick_cpu(void *opaque)
{
    PowerPCCPU *cpu = opaque;

    qemu_cpu_kick(CPU(cpu));
}

static int kvm_ppc_register_host_cpu_type(void);

int kvm_arch_init(KVMState *s)
{
    cap_interrupt_unset = kvm_check_extension(s, KVM_CAP_PPC_UNSET_IRQ);
    cap_interrupt_level = kvm_check_extension(s, KVM_CAP_PPC_IRQ_LEVEL);
    cap_segstate = kvm_check_extension(s, KVM_CAP_PPC_SEGSTATE);
    cap_booke_sregs = kvm_check_extension(s, KVM_CAP_PPC_BOOKE_SREGS);
    cap_ppc_smt = kvm_check_extension(s, KVM_CAP_PPC_SMT);
    cap_ppc_rma = kvm_check_extension(s, KVM_CAP_PPC_RMA);
    cap_spapr_tce = kvm_check_extension(s, KVM_CAP_SPAPR_TCE);
    cap_one_reg = kvm_check_extension(s, KVM_CAP_ONE_REG);
    cap_hior = kvm_check_extension(s, KVM_CAP_PPC_HIOR);

    if (!cap_interrupt_level) {
        fprintf(stderr, "KVM: Couldn't find level irq capability. Expect the "
                        "VM to stall at times!\n");
    }

    kvm_ppc_register_host_cpu_type();

    return 0;
}

static int kvm_arch_sync_sregs(PowerPCCPU *cpu)
{
    CPUPPCState *cenv = &cpu->env;
    CPUState *cs = CPU(cpu);
    struct kvm_sregs sregs;
    int ret;

    if (cenv->excp_model == POWERPC_EXCP_BOOKE) {
        /* What we're really trying to say is "if we're on BookE, we use
           the native PVR for now". This is the only sane way to check
           it though, so we potentially confuse users that they can run
           BookE guests on BookS. Let's hope nobody dares enough :) */
        return 0;
    } else {
        if (!cap_segstate) {
            fprintf(stderr, "kvm error: missing PVR setting capability\n");
            return -ENOSYS;
        }
    }

    ret = kvm_vcpu_ioctl(cs, KVM_GET_SREGS, &sregs);
    if (ret) {
        return ret;
    }

    sregs.pvr = cenv->spr[SPR_PVR];
    return kvm_vcpu_ioctl(cs, KVM_SET_SREGS, &sregs);
}

/* Set up a shared TLB array with KVM */
static int kvm_booke206_tlb_init(PowerPCCPU *cpu)
{
    CPUPPCState *env = &cpu->env;
    CPUState *cs = CPU(cpu);
    struct kvm_book3e_206_tlb_params params = {};
    struct kvm_config_tlb cfg = {};
    struct kvm_enable_cap encap = {};
    unsigned int entries = 0;
    int ret, i;

    if (!kvm_enabled() ||
        !kvm_check_extension(cs->kvm_state, KVM_CAP_SW_TLB)) {
        return 0;
    }

    assert(ARRAY_SIZE(params.tlb_sizes) == BOOKE206_MAX_TLBN);

    for (i = 0; i < BOOKE206_MAX_TLBN; i++) {
        params.tlb_sizes[i] = booke206_tlb_size(env, i);
        params.tlb_ways[i] = booke206_tlb_ways(env, i);
        entries += params.tlb_sizes[i];
    }

    assert(entries == env->nb_tlb);
    assert(sizeof(struct kvm_book3e_206_tlb_entry) == sizeof(ppcmas_tlb_t));

    env->tlb_dirty = true;

    cfg.array = (uintptr_t)env->tlb.tlbm;
    cfg.array_len = sizeof(ppcmas_tlb_t) * entries;
    cfg.params = (uintptr_t)&params;
    cfg.mmu_type = KVM_MMU_FSL_BOOKE_NOHV;

    encap.cap = KVM_CAP_SW_TLB;
    encap.args[0] = (uintptr_t)&cfg;

    ret = kvm_vcpu_ioctl(cs, KVM_ENABLE_CAP, &encap);
    if (ret < 0) {
        fprintf(stderr, "%s: couldn't enable KVM_CAP_SW_TLB: %s\n",
                __func__, strerror(-ret));
        return ret;
    }

    env->kvm_sw_tlb = true;
    return 0;
}


#if defined(TARGET_PPC64)
static void kvm_get_fallback_smmu_info(PowerPCCPU *cpu,
                                       struct kvm_ppc_smmu_info *info)
{
    CPUPPCState *env = &cpu->env;
    CPUState *cs = CPU(cpu);

    memset(info, 0, sizeof(*info));

    /* We don't have the new KVM_PPC_GET_SMMU_INFO ioctl, so
     * need to "guess" what the supported page sizes are.
     *
     * For that to work we make a few assumptions:
     *
     * - If KVM_CAP_PPC_GET_PVINFO is supported we are running "PR"
     *   KVM which only supports 4K and 16M pages, but supports them
     *   regardless of the backing store characteritics. We also don't
     *   support 1T segments.
     *
     *   This is safe as if HV KVM ever supports that capability or PR
     *   KVM grows supports for more page/segment sizes, those versions
     *   will have implemented KVM_CAP_PPC_GET_SMMU_INFO and thus we
     *   will not hit this fallback
     *
     * - Else we are running HV KVM. This means we only support page
     *   sizes that fit in the backing store. Additionally we only
     *   advertize 64K pages if the processor is ARCH 2.06 and we assume
     *   P7 encodings for the SLB and hash table. Here too, we assume
     *   support for any newer processor will mean a kernel that
     *   implements KVM_CAP_PPC_GET_SMMU_INFO and thus doesn't hit
     *   this fallback.
     */
    if (kvm_check_extension(cs->kvm_state, KVM_CAP_PPC_GET_PVINFO)) {
        /* No flags */
        info->flags = 0;
        info->slb_size = 64;

        /* Standard 4k base page size segment */
        info->sps[0].page_shift = 12;
        info->sps[0].slb_enc = 0;
        info->sps[0].enc[0].page_shift = 12;
        info->sps[0].enc[0].pte_enc = 0;

        /* Standard 16M large page size segment */
        info->sps[1].page_shift = 24;
        info->sps[1].slb_enc = SLB_VSID_L;
        info->sps[1].enc[0].page_shift = 24;
        info->sps[1].enc[0].pte_enc = 0;
    } else {
        int i = 0;

        /* HV KVM has backing store size restrictions */
        info->flags = KVM_PPC_PAGE_SIZES_REAL;

        if (env->mmu_model & POWERPC_MMU_1TSEG) {
            info->flags |= KVM_PPC_1T_SEGMENTS;
        }

        if (env->mmu_model == POWERPC_MMU_2_06) {
            info->slb_size = 32;
        } else {
            info->slb_size = 64;
        }

        /* Standard 4k base page size segment */
        info->sps[i].page_shift = 12;
        info->sps[i].slb_enc = 0;
        info->sps[i].enc[0].page_shift = 12;
        info->sps[i].enc[0].pte_enc = 0;
        i++;

        /* 64K on MMU 2.06 */
        if (env->mmu_model == POWERPC_MMU_2_06) {
            info->sps[i].page_shift = 16;
            info->sps[i].slb_enc = 0x110;
            info->sps[i].enc[0].page_shift = 16;
            info->sps[i].enc[0].pte_enc = 1;
            i++;
        }

        /* Standard 16M large page size segment */
        info->sps[i].page_shift = 24;
        info->sps[i].slb_enc = SLB_VSID_L;
        info->sps[i].enc[0].page_shift = 24;
        info->sps[i].enc[0].pte_enc = 0;
    }
}

static void kvm_get_smmu_info(PowerPCCPU *cpu, struct kvm_ppc_smmu_info *info)
{
    CPUState *cs = CPU(cpu);
    int ret;

    if (kvm_check_extension(cs->kvm_state, KVM_CAP_PPC_GET_SMMU_INFO)) {
        ret = kvm_vm_ioctl(cs->kvm_state, KVM_PPC_GET_SMMU_INFO, info);
        if (ret == 0) {
            return;
        }
    }

    kvm_get_fallback_smmu_info(cpu, info);
}

static long getrampagesize(void)
{
    struct statfs fs;
    int ret;

    if (!mem_path) {
        /* guest RAM is backed by normal anonymous pages */
        return getpagesize();
    }

    do {
        ret = statfs(mem_path, &fs);
    } while (ret != 0 && errno == EINTR);

    if (ret != 0) {
        fprintf(stderr, "Couldn't statfs() memory path: %s\n",
                strerror(errno));
        exit(1);
    }

#define HUGETLBFS_MAGIC       0x958458f6

    if (fs.f_type != HUGETLBFS_MAGIC) {
        /* Explicit mempath, but it's ordinary pages */
        return getpagesize();
    }

    /* It's hugepage, return the huge page size */
    return fs.f_bsize;
}

static bool kvm_valid_page_size(uint32_t flags, long rampgsize, uint32_t shift)
{
    if (!(flags & KVM_PPC_PAGE_SIZES_REAL)) {
        return true;
    }

    return (1ul << shift) <= rampgsize;
}

static void kvm_fixup_page_sizes(PowerPCCPU *cpu)
{
    static struct kvm_ppc_smmu_info smmu_info;
    static bool has_smmu_info;
    CPUPPCState *env = &cpu->env;
    long rampagesize;
    int iq, ik, jq, jk;

    /* We only handle page sizes for 64-bit server guests for now */
    if (!(env->mmu_model & POWERPC_MMU_64)) {
        return;
    }

    /* Collect MMU info from kernel if not already */
    if (!has_smmu_info) {
        kvm_get_smmu_info(cpu, &smmu_info);
        has_smmu_info = true;
    }

    rampagesize = getrampagesize();

    /* Convert to QEMU form */
    memset(&env->sps, 0, sizeof(env->sps));

    for (ik = iq = 0; ik < KVM_PPC_PAGE_SIZES_MAX_SZ; ik++) {
        struct ppc_one_seg_page_size *qsps = &env->sps.sps[iq];
        struct kvm_ppc_one_seg_page_size *ksps = &smmu_info.sps[ik];

        if (!kvm_valid_page_size(smmu_info.flags, rampagesize,
                                 ksps->page_shift)) {
            continue;
        }
        qsps->page_shift = ksps->page_shift;
        qsps->slb_enc = ksps->slb_enc;
        for (jk = jq = 0; jk < KVM_PPC_PAGE_SIZES_MAX_SZ; jk++) {
            if (!kvm_valid_page_size(smmu_info.flags, rampagesize,
                                     ksps->enc[jk].page_shift)) {
                continue;
            }
            qsps->enc[jq].page_shift = ksps->enc[jk].page_shift;
            qsps->enc[jq].pte_enc = ksps->enc[jk].pte_enc;
            if (++jq >= PPC_PAGE_SIZES_MAX_SZ) {
                break;
            }
        }
        if (++iq >= PPC_PAGE_SIZES_MAX_SZ) {
            break;
        }
    }
    env->slb_nr = smmu_info.slb_size;
    if (smmu_info.flags & KVM_PPC_1T_SEGMENTS) {
        env->mmu_model |= POWERPC_MMU_1TSEG;
    } else {
        env->mmu_model &= ~POWERPC_MMU_1TSEG;
    }
}
#else /* defined (TARGET_PPC64) */

static inline void kvm_fixup_page_sizes(PowerPCCPU *cpu)
{
}

#endif /* !defined (TARGET_PPC64) */

unsigned long kvm_arch_vcpu_id(CPUState *cpu)
{
    return cpu->cpu_index;
}

int kvm_arch_init_vcpu(CPUState *cs)
{
    PowerPCCPU *cpu = POWERPC_CPU(cs);
    CPUPPCState *cenv = &cpu->env;
    int ret;

    /* Gather server mmu info from KVM and update the CPU state */
    kvm_fixup_page_sizes(cpu);

    /* Synchronize sregs with kvm */
    ret = kvm_arch_sync_sregs(cpu);
    if (ret) {
        return ret;
    }

    idle_timer = qemu_new_timer_ns(vm_clock, kvm_kick_cpu, cpu);

    /* Some targets support access to KVM's guest TLB. */
    switch (cenv->mmu_model) {
    case POWERPC_MMU_BOOKE206:
        ret = kvm_booke206_tlb_init(cpu);
        break;
    default:
        break;
    }

    return ret;
}

void kvm_arch_reset_vcpu(CPUState *cpu)
{
}

static void kvm_sw_tlb_put(PowerPCCPU *cpu)
{
    CPUPPCState *env = &cpu->env;
    CPUState *cs = CPU(cpu);
    struct kvm_dirty_tlb dirty_tlb;
    unsigned char *bitmap;
    int ret;

    if (!env->kvm_sw_tlb) {
        return;
    }

    bitmap = g_malloc((env->nb_tlb + 7) / 8);
    memset(bitmap, 0xFF, (env->nb_tlb + 7) / 8);

    dirty_tlb.bitmap = (uintptr_t)bitmap;
    dirty_tlb.num_dirty = env->nb_tlb;

    ret = kvm_vcpu_ioctl(cs, KVM_DIRTY_TLB, &dirty_tlb);
    if (ret) {
        fprintf(stderr, "%s: KVM_DIRTY_TLB: %s\n",
                __func__, strerror(-ret));
    }

    g_free(bitmap);
}

static void kvm_get_one_spr(CPUState *cs, uint64_t id, int spr)
{
    PowerPCCPU *cpu = POWERPC_CPU(cs);
    CPUPPCState *env = &cpu->env;
    union {
        uint32_t u32;
        uint64_t u64;
    } val;
    struct kvm_one_reg reg = {
        .id = id,
        .addr = (uintptr_t) &val,
    };
    int ret;

    ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &reg);
    if (ret != 0) {
        fprintf(stderr, "Warning: Unable to retrieve SPR %d from KVM: %s\n",
                spr, strerror(errno));
    } else {
        switch (id & KVM_REG_SIZE_MASK) {
        case KVM_REG_SIZE_U32:
            env->spr[spr] = val.u32;
            break;

        case KVM_REG_SIZE_U64:
            env->spr[spr] = val.u64;
            break;

        default:
            /* Don't handle this size yet */
            abort();
        }
    }
}

static void kvm_put_one_spr(CPUState *cs, uint64_t id, int spr)
{
    PowerPCCPU *cpu = POWERPC_CPU(cs);
    CPUPPCState *env = &cpu->env;
    union {
        uint32_t u32;
        uint64_t u64;
    } val;
    struct kvm_one_reg reg = {
        .id = id,
        .addr = (uintptr_t) &val,
    };
    int ret;

    switch (id & KVM_REG_SIZE_MASK) {
    case KVM_REG_SIZE_U32:
        val.u32 = env->spr[spr];
        break;

    case KVM_REG_SIZE_U64:
        val.u64 = env->spr[spr];
        break;

    default:
        /* Don't handle this size yet */
        abort();
    }

    ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &reg);
    if (ret != 0) {
        fprintf(stderr, "Warning: Unable to set SPR %d to KVM: %s\n",
                spr, strerror(errno));
    }
}

static int kvm_put_fp(CPUState *cs)
{
    PowerPCCPU *cpu = POWERPC_CPU(cs);
    CPUPPCState *env = &cpu->env;
    struct kvm_one_reg reg;
    int i;
    int ret;

    if (env->insns_flags & PPC_FLOAT) {
        uint64_t fpscr = env->fpscr;
        bool vsx = !!(env->insns_flags2 & PPC2_VSX);

        reg.id = KVM_REG_PPC_FPSCR;
        reg.addr = (uintptr_t)&fpscr;
        ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &reg);
        if (ret < 0) {
            dprintf("Unable to set FPSCR to KVM: %s\n", strerror(errno));
            return ret;
        }

        for (i = 0; i < 32; i++) {
            uint64_t vsr[2];

            vsr[0] = float64_val(env->fpr[i]);
            vsr[1] = env->vsr[i];
            reg.addr = (uintptr_t) &vsr;
            reg.id = vsx ? KVM_REG_PPC_VSR(i) : KVM_REG_PPC_FPR(i);

            ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &reg);
            if (ret < 0) {
                dprintf("Unable to set %s%d to KVM: %s\n", vsx ? "VSR" : "FPR",
                        i, strerror(errno));
                return ret;
            }
        }
    }

    if (env->insns_flags & PPC_ALTIVEC) {
        reg.id = KVM_REG_PPC_VSCR;
        reg.addr = (uintptr_t)&env->vscr;
        ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &reg);
        if (ret < 0) {
            dprintf("Unable to set VSCR to KVM: %s\n", strerror(errno));
            return ret;
        }

        for (i = 0; i < 32; i++) {
            reg.id = KVM_REG_PPC_VR(i);
            reg.addr = (uintptr_t)&env->avr[i];
            ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &reg);
            if (ret < 0) {
                dprintf("Unable to set VR%d to KVM: %s\n", i, strerror(errno));
                return ret;
            }
        }
    }

    return 0;
}

static int kvm_get_fp(CPUState *cs)
{
    PowerPCCPU *cpu = POWERPC_CPU(cs);
    CPUPPCState *env = &cpu->env;
    struct kvm_one_reg reg;
    int i;
    int ret;

    if (env->insns_flags & PPC_FLOAT) {
        uint64_t fpscr;
        bool vsx = !!(env->insns_flags2 & PPC2_VSX);

        reg.id = KVM_REG_PPC_FPSCR;
        reg.addr = (uintptr_t)&fpscr;
        ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &reg);
        if (ret < 0) {
            dprintf("Unable to get FPSCR from KVM: %s\n", strerror(errno));
            return ret;
        } else {
            env->fpscr = fpscr;
        }

        for (i = 0; i < 32; i++) {
            uint64_t vsr[2];

            reg.addr = (uintptr_t) &vsr;
            reg.id = vsx ? KVM_REG_PPC_VSR(i) : KVM_REG_PPC_FPR(i);

            ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &reg);
            if (ret < 0) {
                dprintf("Unable to get %s%d from KVM: %s\n",
                        vsx ? "VSR" : "FPR", i, strerror(errno));
                return ret;
            } else {
                env->fpr[i] = vsr[0];
                if (vsx) {
                    env->vsr[i] = vsr[1];
                }
            }
        }
    }

    if (env->insns_flags & PPC_ALTIVEC) {
        reg.id = KVM_REG_PPC_VSCR;
        reg.addr = (uintptr_t)&env->vscr;
        ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &reg);
        if (ret < 0) {
            dprintf("Unable to get VSCR from KVM: %s\n", strerror(errno));
            return ret;
        }

        for (i = 0; i < 32; i++) {
            reg.id = KVM_REG_PPC_VR(i);
            reg.addr = (uintptr_t)&env->avr[i];
            ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &reg);
            if (ret < 0) {
                dprintf("Unable to get VR%d from KVM: %s\n",
                        i, strerror(errno));
                return ret;
            }
        }
    }

    return 0;
}

int kvm_arch_put_registers(CPUState *cs, int level)
{
    PowerPCCPU *cpu = POWERPC_CPU(cs);
    CPUPPCState *env = &cpu->env;
    struct kvm_regs regs;
    int ret;
    int i;

    ret = kvm_vcpu_ioctl(cs, KVM_GET_REGS, &regs);
    if (ret < 0) {
        return ret;
    }

    regs.ctr = env->ctr;
    regs.lr  = env->lr;
    regs.xer = cpu_read_xer(env);
    regs.msr = env->msr;
    regs.pc = env->nip;

    regs.srr0 = env->spr[SPR_SRR0];
    regs.srr1 = env->spr[SPR_SRR1];

    regs.sprg0 = env->spr[SPR_SPRG0];
    regs.sprg1 = env->spr[SPR_SPRG1];
    regs.sprg2 = env->spr[SPR_SPRG2];
    regs.sprg3 = env->spr[SPR_SPRG3];
    regs.sprg4 = env->spr[SPR_SPRG4];
    regs.sprg5 = env->spr[SPR_SPRG5];
    regs.sprg6 = env->spr[SPR_SPRG6];
    regs.sprg7 = env->spr[SPR_SPRG7];

    regs.pid = env->spr[SPR_BOOKE_PID];

    for (i = 0;i < 32; i++)
        regs.gpr[i] = env->gpr[i];

    ret = kvm_vcpu_ioctl(cs, KVM_SET_REGS, &regs);
    if (ret < 0)
        return ret;

    kvm_put_fp(cs);

    if (env->tlb_dirty) {
        kvm_sw_tlb_put(cpu);
        env->tlb_dirty = false;
    }

    if (cap_segstate && (level >= KVM_PUT_RESET_STATE)) {
        struct kvm_sregs sregs;

        sregs.pvr = env->spr[SPR_PVR];

        sregs.u.s.sdr1 = env->spr[SPR_SDR1];

        /* Sync SLB */
#ifdef TARGET_PPC64
        for (i = 0; i < 64; i++) {
            sregs.u.s.ppc64.slb[i].slbe = env->slb[i].esid;
            sregs.u.s.ppc64.slb[i].slbv = env->slb[i].vsid;
        }
#endif

        /* Sync SRs */
        for (i = 0; i < 16; i++) {
            sregs.u.s.ppc32.sr[i] = env->sr[i];
        }

        /* Sync BATs */
        for (i = 0; i < 8; i++) {
            /* Beware. We have to swap upper and lower bits here */
            sregs.u.s.ppc32.dbat[i] = ((uint64_t)env->DBAT[0][i] << 32)
                | env->DBAT[1][i];
            sregs.u.s.ppc32.ibat[i] = ((uint64_t)env->IBAT[0][i] << 32)
                | env->IBAT[1][i];
        }

        ret = kvm_vcpu_ioctl(cs, KVM_SET_SREGS, &sregs);
        if (ret) {
            return ret;
        }
    }

    if (cap_hior && (level >= KVM_PUT_RESET_STATE)) {
        kvm_put_one_spr(cs, KVM_REG_PPC_HIOR, SPR_HIOR);
    }

    if (cap_one_reg) {
        int i;

        /* We deliberately ignore errors here, for kernels which have
         * the ONE_REG calls, but don't support the specific
         * registers, there's a reasonable chance things will still
         * work, at least until we try to migrate. */
        for (i = 0; i < 1024; i++) {
            uint64_t id = env->spr_cb[i].one_reg_id;

            if (id != 0) {
                kvm_put_one_spr(cs, id, i);
            }
        }
    }

    return ret;
}

int kvm_arch_get_registers(CPUState *cs)
{
    PowerPCCPU *cpu = POWERPC_CPU(cs);
    CPUPPCState *env = &cpu->env;
    struct kvm_regs regs;
    struct kvm_sregs sregs;
    uint32_t cr;
    int i, ret;

    ret = kvm_vcpu_ioctl(cs, KVM_GET_REGS, &regs);
    if (ret < 0)
        return ret;

    cr = regs.cr;
    for (i = 7; i >= 0; i--) {
        env->crf[i] = cr & 15;
        cr >>= 4;
    }

    env->ctr = regs.ctr;
    env->lr = regs.lr;
    cpu_write_xer(env, regs.xer);
    env->msr = regs.msr;
    env->nip = regs.pc;

    env->spr[SPR_SRR0] = regs.srr0;
    env->spr[SPR_SRR1] = regs.srr1;

    env->spr[SPR_SPRG0] = regs.sprg0;
    env->spr[SPR_SPRG1] = regs.sprg1;
    env->spr[SPR_SPRG2] = regs.sprg2;
    env->spr[SPR_SPRG3] = regs.sprg3;
    env->spr[SPR_SPRG4] = regs.sprg4;
    env->spr[SPR_SPRG5] = regs.sprg5;
    env->spr[SPR_SPRG6] = regs.sprg6;
    env->spr[SPR_SPRG7] = regs.sprg7;

    env->spr[SPR_BOOKE_PID] = regs.pid;

    for (i = 0;i < 32; i++)
        env->gpr[i] = regs.gpr[i];

    kvm_get_fp(cs);

    if (cap_booke_sregs) {
        ret = kvm_vcpu_ioctl(cs, KVM_GET_SREGS, &sregs);
        if (ret < 0) {
            return ret;
        }

        if (sregs.u.e.features & KVM_SREGS_E_BASE) {
            env->spr[SPR_BOOKE_CSRR0] = sregs.u.e.csrr0;
            env->spr[SPR_BOOKE_CSRR1] = sregs.u.e.csrr1;
            env->spr[SPR_BOOKE_ESR] = sregs.u.e.esr;
            env->spr[SPR_BOOKE_DEAR] = sregs.u.e.dear;
            env->spr[SPR_BOOKE_MCSR] = sregs.u.e.mcsr;
            env->spr[SPR_BOOKE_TSR] = sregs.u.e.tsr;
            env->spr[SPR_BOOKE_TCR] = sregs.u.e.tcr;
            env->spr[SPR_DECR] = sregs.u.e.dec;
            env->spr[SPR_TBL] = sregs.u.e.tb & 0xffffffff;
            env->spr[SPR_TBU] = sregs.u.e.tb >> 32;
            env->spr[SPR_VRSAVE] = sregs.u.e.vrsave;
        }

        if (sregs.u.e.features & KVM_SREGS_E_ARCH206) {
            env->spr[SPR_BOOKE_PIR] = sregs.u.e.pir;
            env->spr[SPR_BOOKE_MCSRR0] = sregs.u.e.mcsrr0;
            env->spr[SPR_BOOKE_MCSRR1] = sregs.u.e.mcsrr1;
            env->spr[SPR_BOOKE_DECAR] = sregs.u.e.decar;
            env->spr[SPR_BOOKE_IVPR] = sregs.u.e.ivpr;
        }

        if (sregs.u.e.features & KVM_SREGS_E_64) {
            env->spr[SPR_BOOKE_EPCR] = sregs.u.e.epcr;
        }

        if (sregs.u.e.features & KVM_SREGS_E_SPRG8) {
            env->spr[SPR_BOOKE_SPRG8] = sregs.u.e.sprg8;
        }

        if (sregs.u.e.features & KVM_SREGS_E_IVOR) {
            env->spr[SPR_BOOKE_IVOR0] = sregs.u.e.ivor_low[0];
            env->spr[SPR_BOOKE_IVOR1] = sregs.u.e.ivor_low[1];
            env->spr[SPR_BOOKE_IVOR2] = sregs.u.e.ivor_low[2];
            env->spr[SPR_BOOKE_IVOR3] = sregs.u.e.ivor_low[3];
            env->spr[SPR_BOOKE_IVOR4] = sregs.u.e.ivor_low[4];
            env->spr[SPR_BOOKE_IVOR5] = sregs.u.e.ivor_low[5];
            env->spr[SPR_BOOKE_IVOR6] = sregs.u.e.ivor_low[6];
            env->spr[SPR_BOOKE_IVOR7] = sregs.u.e.ivor_low[7];
            env->spr[SPR_BOOKE_IVOR8] = sregs.u.e.ivor_low[8];
            env->spr[SPR_BOOKE_IVOR9] = sregs.u.e.ivor_low[9];
            env->spr[SPR_BOOKE_IVOR10] = sregs.u.e.ivor_low[10];
            env->spr[SPR_BOOKE_IVOR11] = sregs.u.e.ivor_low[11];
            env->spr[SPR_BOOKE_IVOR12] = sregs.u.e.ivor_low[12];
            env->spr[SPR_BOOKE_IVOR13] = sregs.u.e.ivor_low[13];
            env->spr[SPR_BOOKE_IVOR14] = sregs.u.e.ivor_low[14];
            env->spr[SPR_BOOKE_IVOR15] = sregs.u.e.ivor_low[15];

            if (sregs.u.e.features & KVM_SREGS_E_SPE) {
                env->spr[SPR_BOOKE_IVOR32] = sregs.u.e.ivor_high[0];
                env->spr[SPR_BOOKE_IVOR33] = sregs.u.e.ivor_high[1];
                env->spr[SPR_BOOKE_IVOR34] = sregs.u.e.ivor_high[2];
            }

            if (sregs.u.e.features & KVM_SREGS_E_PM) {
                env->spr[SPR_BOOKE_IVOR35] = sregs.u.e.ivor_high[3];
            }

            if (sregs.u.e.features & KVM_SREGS_E_PC) {
                env->spr[SPR_BOOKE_IVOR36] = sregs.u.e.ivor_high[4];
                env->spr[SPR_BOOKE_IVOR37] = sregs.u.e.ivor_high[5];
            }
        }

        if (sregs.u.e.features & KVM_SREGS_E_ARCH206_MMU) {
            env->spr[SPR_BOOKE_MAS0] = sregs.u.e.mas0;
            env->spr[SPR_BOOKE_MAS1] = sregs.u.e.mas1;
            env->spr[SPR_BOOKE_MAS2] = sregs.u.e.mas2;
            env->spr[SPR_BOOKE_MAS3] = sregs.u.e.mas7_3 & 0xffffffff;
            env->spr[SPR_BOOKE_MAS4] = sregs.u.e.mas4;
            env->spr[SPR_BOOKE_MAS6] = sregs.u.e.mas6;
            env->spr[SPR_BOOKE_MAS7] = sregs.u.e.mas7_3 >> 32;
            env->spr[SPR_MMUCFG] = sregs.u.e.mmucfg;
            env->spr[SPR_BOOKE_TLB0CFG] = sregs.u.e.tlbcfg[0];
            env->spr[SPR_BOOKE_TLB1CFG] = sregs.u.e.tlbcfg[1];
        }

        if (sregs.u.e.features & KVM_SREGS_EXP) {
            env->spr[SPR_BOOKE_EPR] = sregs.u.e.epr;
        }

        if (sregs.u.e.features & KVM_SREGS_E_PD) {
            env->spr[SPR_BOOKE_EPLC] = sregs.u.e.eplc;
            env->spr[SPR_BOOKE_EPSC] = sregs.u.e.epsc;
        }

        if (sregs.u.e.impl_id == KVM_SREGS_E_IMPL_FSL) {
            env->spr[SPR_E500_SVR] = sregs.u.e.impl.fsl.svr;
            env->spr[SPR_Exxx_MCAR] = sregs.u.e.impl.fsl.mcar;
            env->spr[SPR_HID0] = sregs.u.e.impl.fsl.hid0;

            if (sregs.u.e.impl.fsl.features & KVM_SREGS_E_FSL_PIDn) {
                env->spr[SPR_BOOKE_PID1] = sregs.u.e.impl.fsl.pid1;
                env->spr[SPR_BOOKE_PID2] = sregs.u.e.impl.fsl.pid2;
            }
        }
    }

    if (cap_segstate) {
        ret = kvm_vcpu_ioctl(cs, KVM_GET_SREGS, &sregs);
        if (ret < 0) {
            return ret;
        }

        ppc_store_sdr1(env, sregs.u.s.sdr1);

        /* Sync SLB */
#ifdef TARGET_PPC64
        for (i = 0; i < 64; i++) {
            ppc_store_slb(env, sregs.u.s.ppc64.slb[i].slbe,
                               sregs.u.s.ppc64.slb[i].slbv);
        }
#endif

        /* Sync SRs */
        for (i = 0; i < 16; i++) {
            env->sr[i] = sregs.u.s.ppc32.sr[i];
        }

        /* Sync BATs */
        for (i = 0; i < 8; i++) {
            env->DBAT[0][i] = sregs.u.s.ppc32.dbat[i] & 0xffffffff;
            env->DBAT[1][i] = sregs.u.s.ppc32.dbat[i] >> 32;
            env->IBAT[0][i] = sregs.u.s.ppc32.ibat[i] & 0xffffffff;
            env->IBAT[1][i] = sregs.u.s.ppc32.ibat[i] >> 32;
        }
    }

    if (cap_hior) {
        kvm_get_one_spr(cs, KVM_REG_PPC_HIOR, SPR_HIOR);
    }

    if (cap_one_reg) {
        int i;

        /* We deliberately ignore errors here, for kernels which have
         * the ONE_REG calls, but don't support the specific
         * registers, there's a reasonable chance things will still
         * work, at least until we try to migrate. */
        for (i = 0; i < 1024; i++) {
            uint64_t id = env->spr_cb[i].one_reg_id;

            if (id != 0) {
                kvm_get_one_spr(cs, id, i);
            }
        }
    }

    return 0;
}

int kvmppc_set_interrupt(PowerPCCPU *cpu, int irq, int level)
{
    unsigned virq = level ? KVM_INTERRUPT_SET_LEVEL : KVM_INTERRUPT_UNSET;

    if (irq != PPC_INTERRUPT_EXT) {
        return 0;
    }

    if (!kvm_enabled() || !cap_interrupt_unset || !cap_interrupt_level) {
        return 0;
    }

    kvm_vcpu_ioctl(CPU(cpu), KVM_INTERRUPT, &virq);

    return 0;
}

#if defined(TARGET_PPCEMB)
#define PPC_INPUT_INT PPC40x_INPUT_INT
#elif defined(TARGET_PPC64)
#define PPC_INPUT_INT PPC970_INPUT_INT
#else
#define PPC_INPUT_INT PPC6xx_INPUT_INT
#endif

void kvm_arch_pre_run(CPUState *cs, struct kvm_run *run)
{
    PowerPCCPU *cpu = POWERPC_CPU(cs);
    CPUPPCState *env = &cpu->env;
    int r;
    unsigned irq;

    /* PowerPC QEMU tracks the various core input pins (interrupt, critical
     * interrupt, reset, etc) in PPC-specific env->irq_input_state. */
    if (!cap_interrupt_level &&
        run->ready_for_interrupt_injection &&
        (env->interrupt_request & CPU_INTERRUPT_HARD) &&
        (env->irq_input_state & (1<<PPC_INPUT_INT)))
    {
        /* For now KVM disregards the 'irq' argument. However, in the
         * future KVM could cache it in-kernel to avoid a heavyweight exit
         * when reading the UIC.
         */
        irq = KVM_INTERRUPT_SET;

        dprintf("injected interrupt %d\n", irq);
        r = kvm_vcpu_ioctl(cs, KVM_INTERRUPT, &irq);
        if (r < 0) {
            printf("cpu %d fail inject %x\n", cs->cpu_index, irq);
        }

        /* Always wake up soon in case the interrupt was level based */
        qemu_mod_timer(idle_timer, qemu_get_clock_ns(vm_clock) +
                       (get_ticks_per_sec() / 50));
    }

    /* We don't know if there are more interrupts pending after this. However,
     * the guest will return to userspace in the course of handling this one
     * anyways, so we will get a chance to deliver the rest. */
}

void kvm_arch_post_run(CPUState *cpu, struct kvm_run *run)
{
}

int kvm_arch_process_async_events(CPUState *cs)
{
    PowerPCCPU *cpu = POWERPC_CPU(cs);
    return cpu->env.halted;
}

static int kvmppc_handle_halt(CPUPPCState *env)
{
    if (!(env->interrupt_request & CPU_INTERRUPT_HARD) && (msr_ee)) {
        env->halted = 1;
        env->exception_index = EXCP_HLT;
    }

    return 0;
}

/* map dcr access to existing qemu dcr emulation */
static int kvmppc_handle_dcr_read(CPUPPCState *env, uint32_t dcrn, uint32_t *data)
{
    if (ppc_dcr_read(env->dcr_env, dcrn, data) < 0)
        fprintf(stderr, "Read to unhandled DCR (0x%x)\n", dcrn);

    return 0;
}

static int kvmppc_handle_dcr_write(CPUPPCState *env, uint32_t dcrn, uint32_t data)
{
    if (ppc_dcr_write(env->dcr_env, dcrn, data) < 0)
        fprintf(stderr, "Write to unhandled DCR (0x%x)\n", dcrn);

    return 0;
}

int kvm_arch_handle_exit(CPUState *cs, struct kvm_run *run)
{
    PowerPCCPU *cpu = POWERPC_CPU(cs);
    CPUPPCState *env = &cpu->env;
    int ret;

    switch (run->exit_reason) {
    case KVM_EXIT_DCR:
        if (run->dcr.is_write) {
            dprintf("handle dcr write\n");
            ret = kvmppc_handle_dcr_write(env, run->dcr.dcrn, run->dcr.data);
        } else {
            dprintf("handle dcr read\n");
            ret = kvmppc_handle_dcr_read(env, run->dcr.dcrn, &run->dcr.data);
        }
        break;
    case KVM_EXIT_HLT:
        dprintf("handle halt\n");
        ret = kvmppc_handle_halt(env);
        break;
#ifdef CONFIG_PSERIES
    case KVM_EXIT_PAPR_HCALL:
        dprintf("handle PAPR hypercall\n");
        run->papr_hcall.ret = spapr_hypercall(cpu,
                                              run->papr_hcall.nr,
                                              run->papr_hcall.args);
        ret = 0;
        break;
#endif
    case KVM_EXIT_EPR:
        dprintf("handle epr\n");
        run->epr.epr = ldl_phys(env->mpic_iack);
        ret = 0;
        break;
    default:
        fprintf(stderr, "KVM: unknown exit reason %d\n", run->exit_reason);
        ret = -1;
        break;
    }

    return ret;
}

static int read_cpuinfo(const char *field, char *value, int len)
{
    FILE *f;
    int ret = -1;
    int field_len = strlen(field);
    char line[512];

    f = fopen("/proc/cpuinfo", "r");
    if (!f) {
        return -1;
    }

    do {
        if(!fgets(line, sizeof(line), f)) {
            break;
        }
        if (!strncmp(line, field, field_len)) {
            pstrcpy(value, len, line);
            ret = 0;
            break;
        }
    } while(*line);

    fclose(f);

    return ret;
}

uint32_t kvmppc_get_tbfreq(void)
{
    char line[512];
    char *ns;
    uint32_t retval = get_ticks_per_sec();

    if (read_cpuinfo("timebase", line, sizeof(line))) {
        return retval;
    }

    if (!(ns = strchr(line, ':'))) {
        return retval;
    }

    ns++;

    retval = atoi(ns);
    return retval;
}

/* Try to find a device tree node for a CPU with clock-frequency property */
static int kvmppc_find_cpu_dt(char *buf, int buf_len)
{
    struct dirent *dirp;
    DIR *dp;

    if ((dp = opendir(PROC_DEVTREE_CPU)) == NULL) {
        printf("Can't open directory " PROC_DEVTREE_CPU "\n");
        return -1;
    }

    buf[0] = '\0';
    while ((dirp = readdir(dp)) != NULL) {
        FILE *f;
        snprintf(buf, buf_len, "%s%s/clock-frequency", PROC_DEVTREE_CPU,
                 dirp->d_name);
        f = fopen(buf, "r");
        if (f) {
            snprintf(buf, buf_len, "%s%s", PROC_DEVTREE_CPU, dirp->d_name);
            fclose(f);
            break;
        }
        buf[0] = '\0';
    }
    closedir(dp);
    if (buf[0] == '\0') {
        printf("Unknown host!\n");
        return -1;
    }

    return 0;
}

/* Read a CPU node property from the host device tree that's a single
 * integer (32-bit or 64-bit).  Returns 0 if anything goes wrong
 * (can't find or open the property, or doesn't understand the
 * format) */
static uint64_t kvmppc_read_int_cpu_dt(const char *propname)
{
    char buf[PATH_MAX];
    union {
        uint32_t v32;
        uint64_t v64;
    } u;
    FILE *f;
    int len;

    if (kvmppc_find_cpu_dt(buf, sizeof(buf))) {
        return -1;
    }

    strncat(buf, "/", sizeof(buf) - strlen(buf));
    strncat(buf, propname, sizeof(buf) - strlen(buf));

    f = fopen(buf, "rb");
    if (!f) {
        return -1;
    }

    len = fread(&u, 1, sizeof(u), f);
    fclose(f);
    switch (len) {
    case 4:
        /* property is a 32-bit quantity */
        return be32_to_cpu(u.v32);
    case 8:
        return be64_to_cpu(u.v64);
    }

    return 0;
}

uint64_t kvmppc_get_clockfreq(void)
{
    return kvmppc_read_int_cpu_dt("clock-frequency");
}

uint32_t kvmppc_get_vmx(void)
{
    return kvmppc_read_int_cpu_dt("ibm,vmx");
}

uint32_t kvmppc_get_dfp(void)
{
    return kvmppc_read_int_cpu_dt("ibm,dfp");
}

static int kvmppc_get_pvinfo(CPUPPCState *env, struct kvm_ppc_pvinfo *pvinfo)
 {
     PowerPCCPU *cpu = ppc_env_get_cpu(env);
     CPUState *cs = CPU(cpu);

    if (kvm_check_extension(cs->kvm_state, KVM_CAP_PPC_GET_PVINFO) &&
        !kvm_vm_ioctl(cs->kvm_state, KVM_PPC_GET_PVINFO, pvinfo)) {
        return 0;
    }

    return 1;
}

int kvmppc_get_hasidle(CPUPPCState *env)
{
    struct kvm_ppc_pvinfo pvinfo;

    if (!kvmppc_get_pvinfo(env, &pvinfo) &&
        (pvinfo.flags & KVM_PPC_PVINFO_FLAGS_EV_IDLE)) {
        return 1;
    }

    return 0;
}

int kvmppc_get_hypercall(CPUPPCState *env, uint8_t *buf, int buf_len)
{
    uint32_t *hc = (uint32_t*)buf;
    struct kvm_ppc_pvinfo pvinfo;

    if (!kvmppc_get_pvinfo(env, &pvinfo)) {
        memcpy(buf, pvinfo.hcall, buf_len);
        return 0;
    }

    /*
     * Fallback to always fail hypercalls:
     *
     *     li r3, -1
     *     nop
     *     nop
     *     nop
     */

    hc[0] = 0x3860ffff;
    hc[1] = 0x60000000;
    hc[2] = 0x60000000;
    hc[3] = 0x60000000;

    return 0;
}

void kvmppc_set_papr(PowerPCCPU *cpu)
{
    CPUPPCState *env = &cpu->env;
    CPUState *cs = CPU(cpu);
    struct kvm_enable_cap cap = {};
    int ret;

    cap.cap = KVM_CAP_PPC_PAPR;
    ret = kvm_vcpu_ioctl(cs, KVM_ENABLE_CAP, &cap);

    if (ret) {
        cpu_abort(env, "This KVM version does not support PAPR\n");
    }
}

void kvmppc_set_mpic_proxy(PowerPCCPU *cpu, int mpic_proxy)
{
    CPUPPCState *env = &cpu->env;
    CPUState *cs = CPU(cpu);
    struct kvm_enable_cap cap = {};
    int ret;

    cap.cap = KVM_CAP_PPC_EPR;
    cap.args[0] = mpic_proxy;
    ret = kvm_vcpu_ioctl(cs, KVM_ENABLE_CAP, &cap);

    if (ret && mpic_proxy) {
        cpu_abort(env, "This KVM version does not support EPR\n");
    }
}

int kvmppc_smt_threads(void)
{
    return cap_ppc_smt ? cap_ppc_smt : 1;
}

#ifdef TARGET_PPC64
off_t kvmppc_alloc_rma(const char *name, MemoryRegion *sysmem)
{
    void *rma;
    off_t size;
    int fd;
    struct kvm_allocate_rma ret;
    MemoryRegion *rma_region;

    /* If cap_ppc_rma == 0, contiguous RMA allocation is not supported
     * if cap_ppc_rma == 1, contiguous RMA allocation is supported, but
     *                      not necessary on this hardware
     * if cap_ppc_rma == 2, contiguous RMA allocation is needed on this hardware
     *
     * FIXME: We should allow the user to force contiguous RMA
     * allocation in the cap_ppc_rma==1 case.
     */
    if (cap_ppc_rma < 2) {
        return 0;
    }

    fd = kvm_vm_ioctl(kvm_state, KVM_ALLOCATE_RMA, &ret);
    if (fd < 0) {
        fprintf(stderr, "KVM: Error on KVM_ALLOCATE_RMA: %s\n",
                strerror(errno));
        return -1;
    }

    size = MIN(ret.rma_size, 256ul << 20);

    rma = mmap(NULL, size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
    if (rma == MAP_FAILED) {
        fprintf(stderr, "KVM: Error mapping RMA: %s\n", strerror(errno));
        return -1;
    };

    rma_region = g_new(MemoryRegion, 1);
    memory_region_init_ram_ptr(rma_region, name, size, rma);
    vmstate_register_ram_global(rma_region);
    memory_region_add_subregion(sysmem, 0, rma_region);

    return size;
}

uint64_t kvmppc_rma_size(uint64_t current_size, unsigned int hash_shift)
{
    if (cap_ppc_rma >= 2) {
        return current_size;
    }
    return MIN(current_size,
               getrampagesize() << (hash_shift - 7));
}
#endif

void *kvmppc_create_spapr_tce(uint32_t liobn, uint32_t window_size, int *pfd)
{
    struct kvm_create_spapr_tce args = {
        .liobn = liobn,
        .window_size = window_size,
    };
    long len;
    int fd;
    void *table;

    /* Must set fd to -1 so we don't try to munmap when called for
     * destroying the table, which the upper layers -will- do
     */
    *pfd = -1;
    if (!cap_spapr_tce) {
        return NULL;
    }

    fd = kvm_vm_ioctl(kvm_state, KVM_CREATE_SPAPR_TCE, &args);
    if (fd < 0) {
        fprintf(stderr, "KVM: Failed to create TCE table for liobn 0x%x\n",
                liobn);
        return NULL;
    }

    len = (window_size / SPAPR_TCE_PAGE_SIZE) * sizeof(sPAPRTCE);
    /* FIXME: round this up to page size */

    table = mmap(NULL, len, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
    if (table == MAP_FAILED) {
        fprintf(stderr, "KVM: Failed to map TCE table for liobn 0x%x\n",
                liobn);
        close(fd);
        return NULL;
    }

    *pfd = fd;
    return table;
}

int kvmppc_remove_spapr_tce(void *table, int fd, uint32_t window_size)
{
    long len;

    if (fd < 0) {
        return -1;
    }

    len = (window_size / SPAPR_TCE_PAGE_SIZE)*sizeof(sPAPRTCE);
    if ((munmap(table, len) < 0) ||
        (close(fd) < 0)) {
        fprintf(stderr, "KVM: Unexpected error removing TCE table: %s",
                strerror(errno));
        /* Leak the table */
    }

    return 0;
}

int kvmppc_reset_htab(int shift_hint)
{
    uint32_t shift = shift_hint;

    if (!kvm_enabled()) {
        /* Full emulation, tell caller to allocate htab itself */
        return 0;
    }
    if (kvm_check_extension(kvm_state, KVM_CAP_PPC_ALLOC_HTAB)) {
        int ret;
        ret = kvm_vm_ioctl(kvm_state, KVM_PPC_ALLOCATE_HTAB, &shift);
        if (ret == -ENOTTY) {
            /* At least some versions of PR KVM advertise the
             * capability, but don't implement the ioctl().  Oops.
             * Return 0 so that we allocate the htab in qemu, as is
             * correct for PR. */
            return 0;
        } else if (ret < 0) {
            return ret;
        }
        return shift;
    }

    /* We have a kernel that predates the htab reset calls.  For PR
     * KVM, we need to allocate the htab ourselves, for an HV KVM of
     * this era, it has allocated a 16MB fixed size hash table
     * already.  Kernels of this era have the GET_PVINFO capability
     * only on PR, so we use this hack to determine the right
     * answer */
    if (kvm_check_extension(kvm_state, KVM_CAP_PPC_GET_PVINFO)) {
        /* PR - tell caller to allocate htab */
        return 0;
    } else {
        /* HV - assume 16MB kernel allocated htab */
        return 24;
    }
}

static inline uint32_t mfpvr(void)
{
    uint32_t pvr;

    asm ("mfpvr %0"
         : "=r"(pvr));
    return pvr;
}

static void alter_insns(uint64_t *word, uint64_t flags, bool on)
{
    if (on) {
        *word |= flags;
    } else {
        *word &= ~flags;
    }
}

static void kvmppc_host_cpu_initfn(Object *obj)
{
    assert(kvm_enabled());
}

static void kvmppc_host_cpu_class_init(ObjectClass *oc, void *data)
{
    PowerPCCPUClass *pcc = POWERPC_CPU_CLASS(oc);
    uint32_t vmx = kvmppc_get_vmx();
    uint32_t dfp = kvmppc_get_dfp();

    /* Now fix up the class with information we can query from the host */

    if (vmx != -1) {
        /* Only override when we know what the host supports */
        alter_insns(&pcc->insns_flags, PPC_ALTIVEC, vmx > 0);
        alter_insns(&pcc->insns_flags2, PPC2_VSX, vmx > 1);
    }
    if (dfp != -1) {
        /* Only override when we know what the host supports */
        alter_insns(&pcc->insns_flags2, PPC2_DFP, dfp);
    }
}

int kvmppc_fixup_cpu(PowerPCCPU *cpu)
{
    CPUState *cs = CPU(cpu);
    int smt;

    /* Adjust cpu index for SMT */
    smt = kvmppc_smt_threads();
    cs->cpu_index = (cs->cpu_index / smp_threads) * smt
        + (cs->cpu_index % smp_threads);

    return 0;
}

static int kvm_ppc_register_host_cpu_type(void)
{
    TypeInfo type_info = {
        .name = TYPE_HOST_POWERPC_CPU,
        .instance_init = kvmppc_host_cpu_initfn,
        .class_init = kvmppc_host_cpu_class_init,
    };
    uint32_t host_pvr = mfpvr();
    PowerPCCPUClass *pvr_pcc;

    pvr_pcc = ppc_cpu_class_by_pvr(host_pvr);
    if (pvr_pcc == NULL) {
        return -1;
    }
    type_info.parent = object_class_get_name(OBJECT_CLASS(pvr_pcc));
    type_register(&type_info);
    return 0;
}


bool kvm_arch_stop_on_emulation_error(CPUState *cpu)
{
    return true;
}

int kvm_arch_on_sigbus_vcpu(CPUState *cpu, int code, void *addr)
{
    return 1;
}

int kvm_arch_on_sigbus(int code, void *addr)
{
    return 1;
}