/*
 * hosting zSeries kernel virtual machines
 *
 * Copyright IBM Corp. 2008, 2009
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License (version 2 only)
 * as published by the Free Software Foundation.
 *
 *    Author(s): Carsten Otte <cotte@de.ibm.com>
 *               Christian Borntraeger <borntraeger@de.ibm.com>
 *               Heiko Carstens <heiko.carstens@de.ibm.com>
 *               Christian Ehrhardt <ehrhardt@de.ibm.com>
 *               Jason J. Herne <jjherne@us.ibm.com>
 */

#include <linux/compiler.h>
#include <linux/err.h>
#include <linux/fs.h>
#include <linux/hrtimer.h>
#include <linux/init.h>
#include <linux/kvm.h>
#include <linux/kvm_host.h>
#include <linux/mman.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/random.h>
#include <linux/slab.h>
#include <linux/timer.h>
#include <linux/vmalloc.h>
#include <linux/bitmap.h>
#include <linux/sched/signal.h>
#include <linux/string.h>

#include <asm/asm-offsets.h>
#include <asm/lowcore.h>
#include <asm/stp.h>
#include <asm/pgtable.h>
#include <asm/gmap.h>
#include <asm/nmi.h>
#include <asm/switch_to.h>
#include <asm/isc.h>
#include <asm/sclp.h>
#include <asm/cpacf.h>
#include <asm/timex.h>
#include "kvm-s390.h"
#include "gaccess.h"

#define KMSG_COMPONENT "kvm-s390"
#undef pr_fmt
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt

#define CREATE_TRACE_POINTS
#include "trace.h"
#include "trace-s390.h"

#define MEM_OP_MAX_SIZE 65536   /* Maximum transfer size for KVM_S390_MEM_OP */
#define LOCAL_IRQS 32
#define VCPU_IRQS_MAX_BUF (sizeof(struct kvm_s390_irq) * \
                           (KVM_MAX_VCPUS + LOCAL_IRQS))

#define VCPU_STAT(x) offsetof(struct kvm_vcpu, stat.x), KVM_STAT_VCPU

struct kvm_stats_debugfs_item debugfs_entries[] = {
        { "userspace_handled", VCPU_STAT(exit_userspace) },
        { "exit_null", VCPU_STAT(exit_null) },
        { "exit_validity", VCPU_STAT(exit_validity) },
        { "exit_stop_request", VCPU_STAT(exit_stop_request) },
        { "exit_external_request", VCPU_STAT(exit_external_request) },
        { "exit_external_interrupt", VCPU_STAT(exit_external_interrupt) },
        { "exit_instruction", VCPU_STAT(exit_instruction) },
        { "exit_pei", VCPU_STAT(exit_pei) },
        { "exit_program_interruption", VCPU_STAT(exit_program_interruption) },
        { "exit_instr_and_program_int", VCPU_STAT(exit_instr_and_program) },
        { "exit_operation_exception", VCPU_STAT(exit_operation_exception) },
        { "halt_successful_poll", VCPU_STAT(halt_successful_poll) },
        { "halt_attempted_poll", VCPU_STAT(halt_attempted_poll) },
        { "halt_poll_invalid", VCPU_STAT(halt_poll_invalid) },
        { "halt_wakeup", VCPU_STAT(halt_wakeup) },
        { "instruction_lctlg", VCPU_STAT(instruction_lctlg) },
        { "instruction_lctl", VCPU_STAT(instruction_lctl) },
        { "instruction_stctl", VCPU_STAT(instruction_stctl) },
        { "instruction_stctg", VCPU_STAT(instruction_stctg) },
        { "deliver_emergency_signal", VCPU_STAT(deliver_emergency_signal) },
        { "deliver_external_call", VCPU_STAT(deliver_external_call) },
        { "deliver_service_signal", VCPU_STAT(deliver_service_signal) },
        { "deliver_virtio_interrupt", VCPU_STAT(deliver_virtio_interrupt) },
        { "deliver_stop_signal", VCPU_STAT(deliver_stop_signal) },
        { "deliver_prefix_signal", VCPU_STAT(deliver_prefix_signal) },
        { "deliver_restart_signal", VCPU_STAT(deliver_restart_signal) },
        { "deliver_program_interruption", VCPU_STAT(deliver_program_int) },
        { "exit_wait_state", VCPU_STAT(exit_wait_state) },
        { "instruction_pfmf", VCPU_STAT(instruction_pfmf) },
        { "instruction_stidp", VCPU_STAT(instruction_stidp) },
        { "instruction_spx", VCPU_STAT(instruction_spx) },
        { "instruction_stpx", VCPU_STAT(instruction_stpx) },
        { "instruction_stap", VCPU_STAT(instruction_stap) },
        { "instruction_storage_key", VCPU_STAT(instruction_storage_key) },
        { "instruction_ipte_interlock", VCPU_STAT(instruction_ipte_interlock) },
        { "instruction_stsch", VCPU_STAT(instruction_stsch) },
        { "instruction_chsc", VCPU_STAT(instruction_chsc) },
        { "instruction_essa", VCPU_STAT(instruction_essa) },
        { "instruction_stsi", VCPU_STAT(instruction_stsi) },
        { "instruction_stfl", VCPU_STAT(instruction_stfl) },
        { "instruction_tprot", VCPU_STAT(instruction_tprot) },
        { "instruction_sthyi", VCPU_STAT(instruction_sthyi) },
        { "instruction_sie", VCPU_STAT(instruction_sie) },
        { "instruction_sigp_sense", VCPU_STAT(instruction_sigp_sense) },
        { "instruction_sigp_sense_running", VCPU_STAT(instruction_sigp_sense_running) },
        { "instruction_sigp_external_call", VCPU_STAT(instruction_sigp_external_call) },
        { "instruction_sigp_emergency", VCPU_STAT(instruction_sigp_emergency) },
        { "instruction_sigp_cond_emergency", VCPU_STAT(instruction_sigp_cond_emergency) },
        { "instruction_sigp_start", VCPU_STAT(instruction_sigp_start) },
        { "instruction_sigp_stop", VCPU_STAT(instruction_sigp_stop) },
        { "instruction_sigp_stop_store_status", VCPU_STAT(instruction_sigp_stop_store_status) },
        { "instruction_sigp_store_status", VCPU_STAT(instruction_sigp_store_status) },
        { "instruction_sigp_store_adtl_status", VCPU_STAT(instruction_sigp_store_adtl_status) },
        { "instruction_sigp_set_arch", VCPU_STAT(instruction_sigp_arch) },
        { "instruction_sigp_set_prefix", VCPU_STAT(instruction_sigp_prefix) },
        { "instruction_sigp_restart", VCPU_STAT(instruction_sigp_restart) },
        { "instruction_sigp_cpu_reset", VCPU_STAT(instruction_sigp_cpu_reset) },
        { "instruction_sigp_init_cpu_reset", VCPU_STAT(instruction_sigp_init_cpu_reset) },
        { "instruction_sigp_unknown", VCPU_STAT(instruction_sigp_unknown) },
        { "diagnose_10", VCPU_STAT(diagnose_10) },
        { "diagnose_44", VCPU_STAT(diagnose_44) },
        { "diagnose_9c", VCPU_STAT(diagnose_9c) },
        { "diagnose_258", VCPU_STAT(diagnose_258) },
        { "diagnose_308", VCPU_STAT(diagnose_308) },
        { "diagnose_500", VCPU_STAT(diagnose_500) },
        { NULL }
};

struct kvm_s390_tod_clock_ext {
        __u8 epoch_idx;
        __u64 tod;
        __u8 reserved[7];
} __packed;

/* allow nested virtualization in KVM (if enabled by user space) */
static int nested;
module_param(nested, int, S_IRUGO);
MODULE_PARM_DESC(nested, "Nested virtualization support");

/* upper facilities limit for kvm */
unsigned long kvm_s390_fac_list_mask[16] = { FACILITIES_KVM };

unsigned long kvm_s390_fac_list_mask_size(void)
{
        BUILD_BUG_ON(ARRAY_SIZE(kvm_s390_fac_list_mask) > S390_ARCH_FAC_MASK_SIZE_U64);
        return ARRAY_SIZE(kvm_s390_fac_list_mask);
}

/* available cpu features supported by kvm */
static DECLARE_BITMAP(kvm_s390_available_cpu_feat, KVM_S390_VM_CPU_FEAT_NR_BITS);
/* available subfunctions indicated via query / "test bit" */
static struct kvm_s390_vm_cpu_subfunc kvm_s390_available_subfunc;

static struct gmap_notifier gmap_notifier;
static struct gmap_notifier vsie_gmap_notifier;
debug_info_t *kvm_s390_dbf;

/* Section: not file related */
int kvm_arch_hardware_enable(void)
{
        /* every s390 is virtualization enabled ;-) */
        return 0;
}

static void kvm_gmap_notifier(struct gmap *gmap, unsigned long start,
                              unsigned long end);

/*
 * This callback is executed during stop_machine(). All CPUs are therefore
 * temporarily stopped. In order not to change guest behavior, we have to
 * disable preemption whenever we touch the epoch of kvm and the VCPUs,
 * so a CPU won't be stopped while calculating with the epoch.
 */
static int kvm_clock_sync(struct notifier_block *notifier, unsigned long val,
                          void *v)
{
        struct kvm *kvm;
        struct kvm_vcpu *vcpu;
        int i;
        unsigned long long *delta = v;

        list_for_each_entry(kvm, &vm_list, vm_list) {
                kvm->arch.epoch -= *delta;
                kvm_for_each_vcpu(i, vcpu, kvm) {
                        vcpu->arch.sie_block->epoch -= *delta;
                        if (vcpu->arch.cputm_enabled)
                                vcpu->arch.cputm_start += *delta;
                        if (vcpu->arch.vsie_block)
                                vcpu->arch.vsie_block->epoch -= *delta;
                }
        }
        return NOTIFY_OK;
}

static struct notifier_block kvm_clock_notifier = {
        .notifier_call = kvm_clock_sync,
};

int kvm_arch_hardware_setup(void)
{
        gmap_notifier.notifier_call = kvm_gmap_notifier;
        gmap_register_pte_notifier(&gmap_notifier);
        vsie_gmap_notifier.notifier_call = kvm_s390_vsie_gmap_notifier;
        gmap_register_pte_notifier(&vsie_gmap_notifier);
        atomic_notifier_chain_register(&s390_epoch_delta_notifier,
                                       &kvm_clock_notifier);
        return 0;
}

void kvm_arch_hardware_unsetup(void)
{
        gmap_unregister_pte_notifier(&gmap_notifier);
        gmap_unregister_pte_notifier(&vsie_gmap_notifier);
        atomic_notifier_chain_unregister(&s390_epoch_delta_notifier,
                                         &kvm_clock_notifier);
}

static void allow_cpu_feat(unsigned long nr)
{
        set_bit_inv(nr, kvm_s390_available_cpu_feat);
}

static inline int plo_test_bit(unsigned char nr)
{
        register unsigned long r0 asm("0") = (unsigned long) nr | 0x100;
        int cc;

        asm volatile(
                /* Parameter registers are ignored for "test bit" */
                "       plo     0,0,0,0(0)\n"
                "       ipm     %0\n"
                "       srl     %0,28\n"
                : "=d" (cc)
                : "d" (r0)
                : "cc");
        return cc == 0;
}

static void kvm_s390_cpu_feat_init(void)
{
        int i;

        for (i = 0; i < 256; ++i) {
                if (plo_test_bit(i))
                        kvm_s390_available_subfunc.plo[i >> 3] |= 0x80 >> (i & 7);
        }

        if (test_facility(28)) /* TOD-clock steering */
                ptff(kvm_s390_available_subfunc.ptff,
                     sizeof(kvm_s390_available_subfunc.ptff),
                     PTFF_QAF);

        if (test_facility(17)) { /* MSA */
                __cpacf_query(CPACF_KMAC, (cpacf_mask_t *)
                              kvm_s390_available_subfunc.kmac);
                __cpacf_query(CPACF_KMC, (cpacf_mask_t *)
                              kvm_s390_available_subfunc.kmc);
                __cpacf_query(CPACF_KM, (cpacf_mask_t *)
                              kvm_s390_available_subfunc.km);
                __cpacf_query(CPACF_KIMD, (cpacf_mask_t *)
                              kvm_s390_available_subfunc.kimd);
                __cpacf_query(CPACF_KLMD, (cpacf_mask_t *)
                              kvm_s390_available_subfunc.klmd);
        }
        if (test_facility(76)) /* MSA3 */
                __cpacf_query(CPACF_PCKMO, (cpacf_mask_t *)
                              kvm_s390_available_subfunc.pckmo);
        if (test_facility(77)) { /* MSA4 */
                __cpacf_query(CPACF_KMCTR, (cpacf_mask_t *)
                              kvm_s390_available_subfunc.kmctr);
                __cpacf_query(CPACF_KMF, (cpacf_mask_t *)
                              kvm_s390_available_subfunc.kmf);
                __cpacf_query(CPACF_KMO, (cpacf_mask_t *)
                              kvm_s390_available_subfunc.kmo);
                __cpacf_query(CPACF_PCC, (cpacf_mask_t *)
                              kvm_s390_available_subfunc.pcc);
        }
        if (test_facility(57)) /* MSA5 */
                __cpacf_query(CPACF_PRNO, (cpacf_mask_t *)
                              kvm_s390_available_subfunc.ppno);

        if (test_facility(146)) /* MSA8 */
                __cpacf_query(CPACF_KMA, (cpacf_mask_t *)
                              kvm_s390_available_subfunc.kma);

        if (MACHINE_HAS_ESOP)
                allow_cpu_feat(KVM_S390_VM_CPU_FEAT_ESOP);
        /*
         * We need SIE support, ESOP (PROT_READ protection for gmap_shadow),
         * 64bit SCAO (SCA passthrough) and IDTE (for gmap_shadow unshadowing).
         */
        if (!sclp.has_sief2 || !MACHINE_HAS_ESOP || !sclp.has_64bscao ||
            !test_facility(3) || !nested)
                return;
        allow_cpu_feat(KVM_S390_VM_CPU_FEAT_SIEF2);
        if (sclp.has_64bscao)
                allow_cpu_feat(KVM_S390_VM_CPU_FEAT_64BSCAO);
        if (sclp.has_siif)
                allow_cpu_feat(KVM_S390_VM_CPU_FEAT_SIIF);
        if (sclp.has_gpere)
                allow_cpu_feat(KVM_S390_VM_CPU_FEAT_GPERE);
        if (sclp.has_gsls)
                allow_cpu_feat(KVM_S390_VM_CPU_FEAT_GSLS);
        if (sclp.has_ib)
                allow_cpu_feat(KVM_S390_VM_CPU_FEAT_IB);
        if (sclp.has_cei)
                allow_cpu_feat(KVM_S390_VM_CPU_FEAT_CEI);
        if (sclp.has_ibs)
                allow_cpu_feat(KVM_S390_VM_CPU_FEAT_IBS);
        if (sclp.has_kss)
                allow_cpu_feat(KVM_S390_VM_CPU_FEAT_KSS);
        /*
         * KVM_S390_VM_CPU_FEAT_SKEY: Wrong shadow of PTE.I bits will make
         * all skey handling functions read/set the skey from the PGSTE
         * instead of the real storage key.
         *
         * KVM_S390_VM_CPU_FEAT_CMMA: Wrong shadow of PTE.I bits will make
         * pages being detected as preserved although they are resident.
         *
         * KVM_S390_VM_CPU_FEAT_PFMFI: Wrong shadow of PTE.I bits will
         * have the same effect as for KVM_S390_VM_CPU_FEAT_SKEY.
         *
         * For KVM_S390_VM_CPU_FEAT_SKEY, KVM_S390_VM_CPU_FEAT_CMMA and
         * KVM_S390_VM_CPU_FEAT_PFMFI, all PTE.I and PGSTE bits have to be
         * correctly shadowed. We can do that for the PGSTE but not for PTE.I.
         *
         * KVM_S390_VM_CPU_FEAT_SIGPIF: Wrong SCB addresses in the SCA. We
         * cannot easily shadow the SCA because of the ipte lock.
         */
}

int kvm_arch_init(void *opaque)
{
        kvm_s390_dbf = debug_register("kvm-trace", 32, 1, 7 * sizeof(long));
        if (!kvm_s390_dbf)
                return -ENOMEM;

        if (debug_register_view(kvm_s390_dbf, &debug_sprintf_view)) {
                debug_unregister(kvm_s390_dbf);
                return -ENOMEM;
        }

        kvm_s390_cpu_feat_init();

        /* Register floating interrupt controller interface. */
        return kvm_register_device_ops(&kvm_flic_ops, KVM_DEV_TYPE_FLIC);
}

void kvm_arch_exit(void)
{
        debug_unregister(kvm_s390_dbf);
}

/* Section: device related */
long kvm_arch_dev_ioctl(struct file *filp,
                        unsigned int ioctl, unsigned long arg)
{
        if (ioctl == KVM_S390_ENABLE_SIE)
                return s390_enable_sie();
        return -EINVAL;
}

int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
{
        int r;

        switch (ext) {
        case KVM_CAP_S390_PSW:
        case KVM_CAP_S390_GMAP:
        case KVM_CAP_SYNC_MMU:
#ifdef CONFIG_KVM_S390_UCONTROL
        case KVM_CAP_S390_UCONTROL:
#endif
        case KVM_CAP_ASYNC_PF:
        case KVM_CAP_SYNC_REGS:
        case KVM_CAP_ONE_REG:
        case KVM_CAP_ENABLE_CAP:
        case KVM_CAP_S390_CSS_SUPPORT:
        case KVM_CAP_IOEVENTFD:
        case KVM_CAP_DEVICE_CTRL:
        case KVM_CAP_ENABLE_CAP_VM:
        case KVM_CAP_S390_IRQCHIP:
        case KVM_CAP_VM_ATTRIBUTES:
        case KVM_CAP_MP_STATE:
        case KVM_CAP_IMMEDIATE_EXIT:
        case KVM_CAP_S390_INJECT_IRQ:
        case KVM_CAP_S390_USER_SIGP:
        case KVM_CAP_S390_USER_STSI:
        case KVM_CAP_S390_SKEYS:
        case KVM_CAP_S390_IRQ_STATE:
        case KVM_CAP_S390_USER_INSTR0:
        case KVM_CAP_S390_CMMA_MIGRATION:
        case KVM_CAP_S390_AIS:
                r = 1;
                break;
        case KVM_CAP_S390_MEM_OP:
                r = MEM_OP_MAX_SIZE;
                break;
        case KVM_CAP_NR_VCPUS:
        case KVM_CAP_MAX_VCPUS:
                r = KVM_S390_BSCA_CPU_SLOTS;
                if (!kvm_s390_use_sca_entries())
                        r = KVM_MAX_VCPUS;
                else if (sclp.has_esca && sclp.has_64bscao)
                        r = KVM_S390_ESCA_CPU_SLOTS;
                break;
        case KVM_CAP_NR_MEMSLOTS:
                r = KVM_USER_MEM_SLOTS;
                break;
        case KVM_CAP_S390_COW:
                r = MACHINE_HAS_ESOP;
                break;
        case KVM_CAP_S390_VECTOR_REGISTERS:
                r = MACHINE_HAS_VX;
                break;
        case KVM_CAP_S390_RI:
                r = test_facility(64);
                break;
        case KVM_CAP_S390_GS:
                r = test_facility(133);
                break;
        default:
                r = 0;
        }
        return r;
}

static void kvm_s390_sync_dirty_log(struct kvm *kvm,
                                        struct kvm_memory_slot *memslot)
{
        gfn_t cur_gfn, last_gfn;
        unsigned long address;
        struct gmap *gmap = kvm->arch.gmap;

        /* Loop over all guest pages */
        last_gfn = memslot->base_gfn + memslot->npages;
        for (cur_gfn = memslot->base_gfn; cur_gfn <= last_gfn; cur_gfn++) {
                address = gfn_to_hva_memslot(memslot, cur_gfn);

                if (test_and_clear_guest_dirty(gmap->mm, address))
                        mark_page_dirty(kvm, cur_gfn);
                if (fatal_signal_pending(current))
                        return;
                cond_resched();
        }
}

/* Section: vm related */
static void sca_del_vcpu(struct kvm_vcpu *vcpu);

/*
 * Get (and clear) the dirty memory log for a memory slot.
 */
int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
                               struct kvm_dirty_log *log)
{
        int r;
        unsigned long n;
        struct kvm_memslots *slots;
        struct kvm_memory_slot *memslot;
        int is_dirty = 0;

        if (kvm_is_ucontrol(kvm))
                return -EINVAL;

        mutex_lock(&kvm->slots_lock);

        r = -EINVAL;
        if (log->slot >= KVM_USER_MEM_SLOTS)
                goto out;

        slots = kvm_memslots(kvm);
        memslot = id_to_memslot(slots, log->slot);
        r = -ENOENT;
        if (!memslot->dirty_bitmap)
                goto out;

        kvm_s390_sync_dirty_log(kvm, memslot);
        r = kvm_get_dirty_log(kvm, log, &is_dirty);
        if (r)
                goto out;

        /* Clear the dirty log */
        if (is_dirty) {
                n = kvm_dirty_bitmap_bytes(memslot);
                memset(memslot->dirty_bitmap, 0, n);
        }
        r = 0;
out:
        mutex_unlock(&kvm->slots_lock);
        return r;
}

static void icpt_operexc_on_all_vcpus(struct kvm *kvm)
{
        unsigned int i;
        struct kvm_vcpu *vcpu;

        kvm_for_each_vcpu(i, vcpu, kvm) {
                kvm_s390_sync_request(KVM_REQ_ICPT_OPEREXC, vcpu);
        }
}

static int kvm_vm_ioctl_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap)
{
        int r;

        if (cap->flags)
                return -EINVAL;

        switch (cap->cap) {
        case KVM_CAP_S390_IRQCHIP:
                VM_EVENT(kvm, 3, "%s", "ENABLE: CAP_S390_IRQCHIP");
                kvm->arch.use_irqchip = 1;
                r = 0;
                break;
        case KVM_CAP_S390_USER_SIGP:
                VM_EVENT(kvm, 3, "%s", "ENABLE: CAP_S390_USER_SIGP");
                kvm->arch.user_sigp = 1;
                r = 0;
                break;
        case KVM_CAP_S390_VECTOR_REGISTERS:
                mutex_lock(&kvm->lock);
                if (kvm->created_vcpus) {
                        r = -EBUSY;
                } else if (MACHINE_HAS_VX) {
                        set_kvm_facility(kvm->arch.model.fac_mask, 129);
                        set_kvm_facility(kvm->arch.model.fac_list, 129);
                        if (test_facility(134)) {
                                set_kvm_facility(kvm->arch.model.fac_mask, 134);
                                set_kvm_facility(kvm->arch.model.fac_list, 134);
                        }
                        if (test_facility(135)) {
                                set_kvm_facility(kvm->arch.model.fac_mask, 135);
                                set_kvm_facility(kvm->arch.model.fac_list, 135);
                        }
                        r = 0;
                } else
                        r = -EINVAL;
                mutex_unlock(&kvm->lock);
                VM_EVENT(kvm, 3, "ENABLE: CAP_S390_VECTOR_REGISTERS %s",
                         r ? "(not available)" : "(success)");
                break;
        case KVM_CAP_S390_RI:
                r = -EINVAL;
                mutex_lock(&kvm->lock);
                if (kvm->created_vcpus) {
                        r = -EBUSY;
                } else if (test_facility(64)) {
                        set_kvm_facility(kvm->arch.model.fac_mask, 64);
                        set_kvm_facility(kvm->arch.model.fac_list, 64);
                        r = 0;
                }
                mutex_unlock(&kvm->lock);
                VM_EVENT(kvm, 3, "ENABLE: CAP_S390_RI %s",
                         r ? "(not available)" : "(success)");
                break;
        case KVM_CAP_S390_AIS:
                mutex_lock(&kvm->lock);
                if (kvm->created_vcpus) {
                        r = -EBUSY;
                } else {
                        set_kvm_facility(kvm->arch.model.fac_mask, 72);
                        set_kvm_facility(kvm->arch.model.fac_list, 72);
                        r = 0;
                }
                mutex_unlock(&kvm->lock);
                VM_EVENT(kvm, 3, "ENABLE: AIS %s",
                         r ? "(not available)" : "(success)");
                break;
        case KVM_CAP_S390_GS:
                r = -EINVAL;
                mutex_lock(&kvm->lock);
                if (atomic_read(&kvm->online_vcpus)) {
                        r = -EBUSY;
                } else if (test_facility(133)) {
                        set_kvm_facility(kvm->arch.model.fac_mask, 133);
                        set_kvm_facility(kvm->arch.model.fac_list, 133);
                        r = 0;
                }
                mutex_unlock(&kvm->lock);
                VM_EVENT(kvm, 3, "ENABLE: CAP_S390_GS %s",
                         r ? "(not available)" : "(success)");
                break;
        case KVM_CAP_S390_USER_STSI:
                VM_EVENT(kvm, 3, "%s", "ENABLE: CAP_S390_USER_STSI");
                kvm->arch.user_stsi = 1;
                r = 0;
                break;
        case KVM_CAP_S390_USER_INSTR0:
                VM_EVENT(kvm, 3, "%s", "ENABLE: CAP_S390_USER_INSTR0");
                kvm->arch.user_instr0 = 1;
                icpt_operexc_on_all_vcpus(kvm);
                r = 0;
                break;
        default:
                r = -EINVAL;
                break;
        }
        return r;
}

static int kvm_s390_get_mem_control(struct kvm *kvm, struct kvm_device_attr *attr)
{
        int ret;

        switch (attr->attr) {
        case KVM_S390_VM_MEM_LIMIT_SIZE:
                ret = 0;
                VM_EVENT(kvm, 3, "QUERY: max guest memory: %lu bytes",
                         kvm->arch.mem_limit);
                if (put_user(kvm->arch.mem_limit, (u64 __user *)attr->addr))
                        ret = -EFAULT;
                break;
        default:
                ret = -ENXIO;
                break;
        }
        return ret;
}

static int kvm_s390_set_mem_control(struct kvm *kvm, struct kvm_device_attr *attr)
{
        int ret;
        unsigned int idx;
        switch (attr->attr) {
        case KVM_S390_VM_MEM_ENABLE_CMMA:
                ret = -ENXIO;
                if (!sclp.has_cmma)
                        break;

                ret = -EBUSY;
                VM_EVENT(kvm, 3, "%s", "ENABLE: CMMA support");
                mutex_lock(&kvm->lock);
                if (!kvm->created_vcpus) {
                        kvm->arch.use_cmma = 1;
                        ret = 0;
                }
                mutex_unlock(&kvm->lock);
                break;
        case KVM_S390_VM_MEM_CLR_CMMA:
                ret = -ENXIO;
                if (!sclp.has_cmma)
                        break;
                ret = -EINVAL;
                if (!kvm->arch.use_cmma)
                        break;

                VM_EVENT(kvm, 3, "%s", "RESET: CMMA states");
                mutex_lock(&kvm->lock);
                idx = srcu_read_lock(&kvm->srcu);
                s390_reset_cmma(kvm->arch.gmap->mm);
                srcu_read_unlock(&kvm->srcu, idx);
                mutex_unlock(&kvm->lock);
                ret = 0;
                break;
        case KVM_S390_VM_MEM_LIMIT_SIZE: {
                unsigned long new_limit;

                if (kvm_is_ucontrol(kvm))
                        return -EINVAL;

                if (get_user(new_limit, (u64 __user *)attr->addr))
                        return -EFAULT;

                if (kvm->arch.mem_limit != KVM_S390_NO_MEM_LIMIT &&
                    new_limit > kvm->arch.mem_limit)
                        return -E2BIG;

                if (!new_limit)
                        return -EINVAL;

                /* gmap_create takes last usable address */
                if (new_limit != KVM_S390_NO_MEM_LIMIT)
                        new_limit -= 1;

                ret = -EBUSY;
                mutex_lock(&kvm->lock);
                if (!kvm->created_vcpus) {
                        /* gmap_create will round the limit up */
                        struct gmap *new = gmap_create(current->mm, new_limit);

                        if (!new) {
                                ret = -ENOMEM;
                        } else {
                                gmap_remove(kvm->arch.gmap);
                                new->private = kvm;
                                kvm->arch.gmap = new;
                                ret = 0;
                        }
                }
                mutex_unlock(&kvm->lock);
                VM_EVENT(kvm, 3, "SET: max guest address: %lu", new_limit);
                VM_EVENT(kvm, 3, "New guest asce: 0x%pK",
                         (void *) kvm->arch.gmap->asce);
                break;
        }
        default:
                ret = -ENXIO;
                break;
        }
        return ret;
}

static void kvm_s390_vcpu_crypto_setup(struct kvm_vcpu *vcpu);

static int kvm_s390_vm_set_crypto(struct kvm *kvm, struct kvm_device_attr *attr)
{
        struct kvm_vcpu *vcpu;
        int i;

        if (!test_kvm_facility(kvm, 76))
                return -EINVAL;

        mutex_lock(&kvm->lock);
        switch (attr->attr) {
        case KVM_S390_VM_CRYPTO_ENABLE_AES_KW:
                get_random_bytes(
                        kvm->arch.crypto.crycb->aes_wrapping_key_mask,
                        sizeof(kvm->arch.crypto.crycb->aes_wrapping_key_mask));
                kvm->arch.crypto.aes_kw = 1;
                VM_EVENT(kvm, 3, "%s", "ENABLE: AES keywrapping support");
                break;
        case KVM_S390_VM_CRYPTO_ENABLE_DEA_KW:
                get_random_bytes(
                        kvm->arch.crypto.crycb->dea_wrapping_key_mask,
                        sizeof(kvm->arch.crypto.crycb->dea_wrapping_key_mask));
                kvm->arch.crypto.dea_kw = 1;
                VM_EVENT(kvm, 3, "%s", "ENABLE: DEA keywrapping support");
                break;
        case KVM_S390_VM_CRYPTO_DISABLE_AES_KW:
                kvm->arch.crypto.aes_kw = 0;
                memset(kvm->arch.crypto.crycb->aes_wrapping_key_mask, 0,
                        sizeof(kvm->arch.crypto.crycb->aes_wrapping_key_mask));
                VM_EVENT(kvm, 3, "%s", "DISABLE: AES keywrapping support");
                break;
        case KVM_S390_VM_CRYPTO_DISABLE_DEA_KW:
                kvm->arch.crypto.dea_kw = 0;
                memset(kvm->arch.crypto.crycb->dea_wrapping_key_mask, 0,
                        sizeof(kvm->arch.crypto.crycb->dea_wrapping_key_mask));
                VM_EVENT(kvm, 3, "%s", "DISABLE: DEA keywrapping support");
                break;
        default:
                mutex_unlock(&kvm->lock);
                return -ENXIO;
        }

        kvm_for_each_vcpu(i, vcpu, kvm) {
                kvm_s390_vcpu_crypto_setup(vcpu);
                exit_sie(vcpu);
        }
        mutex_unlock(&kvm->lock);
        return 0;
}

static void kvm_s390_sync_request_broadcast(struct kvm *kvm, int req)
{
        int cx;
        struct kvm_vcpu *vcpu;

        kvm_for_each_vcpu(cx, vcpu, kvm)
                kvm_s390_sync_request(req, vcpu);
}

/*
 * Must be called with kvm->srcu held to avoid races on memslots, and with
 * kvm->lock to avoid races with ourselves and kvm_s390_vm_stop_migration.
 */
static int kvm_s390_vm_start_migration(struct kvm *kvm)
{
        struct kvm_s390_migration_state *mgs;
        struct kvm_memory_slot *ms;
        /* should be the only one */
        struct kvm_memslots *slots;
        unsigned long ram_pages;
        int slotnr;

        /* migration mode already enabled */
        if (kvm->arch.migration_state)
                return 0;

        slots = kvm_memslots(kvm);
        if (!slots || !slots->used_slots)
                return -EINVAL;

        mgs = kzalloc(sizeof(*mgs), GFP_KERNEL);
        if (!mgs)
                return -ENOMEM;
        kvm->arch.migration_state = mgs;

        if (kvm->arch.use_cmma) {
                /*
                 * Get the last slot. They should be sorted by base_gfn, so the
                 * last slot is also the one at the end of the address space.
                 * We have verified above that at least one slot is present.
                 */
                ms = slots->memslots + slots->used_slots - 1;
                /* round up so we only use full longs */
                ram_pages = roundup(ms->base_gfn + ms->npages, BITS_PER_LONG);
                /* allocate enough bytes to store all the bits */
                mgs->pgste_bitmap = vmalloc(ram_pages / 8);
                if (!mgs->pgste_bitmap) {
                        kfree(mgs);
                        kvm->arch.migration_state = NULL;
                        return -ENOMEM;
                }

                mgs->bitmap_size = ram_pages;
                atomic64_set(&mgs->dirty_pages, ram_pages);
                /* mark all the pages in active slots as dirty */
                for (slotnr = 0; slotnr < slots->used_slots; slotnr++) {
                        ms = slots->memslots + slotnr;
                        bitmap_set(mgs->pgste_bitmap, ms->base_gfn, ms->npages);
                }

                kvm_s390_sync_request_broadcast(kvm, KVM_REQ_START_MIGRATION);
        }
        return 0;
}

/*
 * Must be called with kvm->lock to avoid races with ourselves and
 * kvm_s390_vm_start_migration.
 */
static int kvm_s390_vm_stop_migration(struct kvm *kvm)
{
        struct kvm_s390_migration_state *mgs;

        /* migration mode already disabled */
        if (!kvm->arch.migration_state)
                return 0;
        mgs = kvm->arch.migration_state;
        kvm->arch.migration_state = NULL;

        if (kvm->arch.use_cmma) {
                kvm_s390_sync_request_broadcast(kvm, KVM_REQ_STOP_MIGRATION);
                vfree(mgs->pgste_bitmap);
        }
        kfree(mgs);
        return 0;
}

static int kvm_s390_vm_set_migration(struct kvm *kvm,
                                     struct kvm_device_attr *attr)
{
        int idx, res = -ENXIO;

        mutex_lock(&kvm->lock);
        switch (attr->attr) {
        case KVM_S390_VM_MIGRATION_START:
                idx = srcu_read_lock(&kvm->srcu);
                res = kvm_s390_vm_start_migration(kvm);
                srcu_read_unlock(&kvm->srcu, idx);
                break;
        case KVM_S390_VM_MIGRATION_STOP:
                res = kvm_s390_vm_stop_migration(kvm);
                break;
        default:
                break;
        }
        mutex_unlock(&kvm->lock);

        return res;
}

static int kvm_s390_vm_get_migration(struct kvm *kvm,
                                     struct kvm_device_attr *attr)
{
        u64 mig = (kvm->arch.migration_state != NULL);

        if (attr->attr != KVM_S390_VM_MIGRATION_STATUS)
                return -ENXIO;

        if (copy_to_user((void __user *)attr->addr, &mig, sizeof(mig)))
                return -EFAULT;
        return 0;
}

static int kvm_s390_set_tod_ext(struct kvm *kvm, struct kvm_device_attr *attr)
{
        struct kvm_s390_vm_tod_clock gtod;

        if (copy_from_user(&gtod, (void __user *)attr->addr, sizeof(gtod)))
                return -EFAULT;

        if (test_kvm_facility(kvm, 139))
                kvm_s390_set_tod_clock_ext(kvm, &gtod);
        else if (gtod.epoch_idx == 0)
                kvm_s390_set_tod_clock(kvm, gtod.tod);
        else
                return -EINVAL;

        VM_EVENT(kvm, 3, "SET: TOD extension: 0x%x, TOD base: 0x%llx",
                gtod.epoch_idx, gtod.tod);

        return 0;
}

static int kvm_s390_set_tod_high(struct kvm *kvm, struct kvm_device_attr *attr)
{
        u8 gtod_high;

        if (copy_from_user(&gtod_high, (void __user *)attr->addr,
                                           sizeof(gtod_high)))
                return -EFAULT;

        if (gtod_high != 0)
                return -EINVAL;
        VM_EVENT(kvm, 3, "SET: TOD extension: 0x%x", gtod_high);

        return 0;
}

static int kvm_s390_set_tod_low(struct kvm *kvm, struct kvm_device_attr *attr)
{
        u64 gtod;

        if (copy_from_user(&gtod, (void __user *)attr->addr, sizeof(gtod)))
                return -EFAULT;

        kvm_s390_set_tod_clock(kvm, gtod);
        VM_EVENT(kvm, 3, "SET: TOD base: 0x%llx", gtod);
        return 0;
}

static int kvm_s390_set_tod(struct kvm *kvm, struct kvm_device_attr *attr)
{
        int ret;

        if (attr->flags)
                return -EINVAL;

        switch (attr->attr) {
        case KVM_S390_VM_TOD_EXT:
                ret = kvm_s390_set_tod_ext(kvm, attr);
                break;
        case KVM_S390_VM_TOD_HIGH:
                ret = kvm_s390_set_tod_high(kvm, attr);
                break;
        case KVM_S390_VM_TOD_LOW:
                ret = kvm_s390_set_tod_low(kvm, attr);
                break;
        default:
                ret = -ENXIO;
                break;
        }
        return ret;
}

static void kvm_s390_get_tod_clock_ext(struct kvm *kvm,
                                        struct kvm_s390_vm_tod_clock *gtod)
{
        struct kvm_s390_tod_clock_ext htod;

        preempt_disable();

        get_tod_clock_ext((char *)&htod);

        gtod->tod = htod.tod + kvm->arch.epoch;
        gtod->epoch_idx = htod.epoch_idx + kvm->arch.epdx;

        if (gtod->tod < htod.tod)
                gtod->epoch_idx += 1;

        preempt_enable();
}

static int kvm_s390_get_tod_ext(struct kvm *kvm, struct kvm_device_attr *attr)
{
        struct kvm_s390_vm_tod_clock gtod;

        memset(&gtod, 0, sizeof(gtod));

        if (test_kvm_facility(kvm, 139))
                kvm_s390_get_tod_clock_ext(kvm, &gtod);
        else
                gtod.tod = kvm_s390_get_tod_clock_fast(kvm);

        if (copy_to_user((void __user *)attr->addr, &gtod, sizeof(gtod)))
                return -EFAULT;

        VM_EVENT(kvm, 3, "QUERY: TOD extension: 0x%x, TOD base: 0x%llx",
                gtod.epoch_idx, gtod.tod);
        return 0;
}

static int kvm_s390_get_tod_high(struct kvm *kvm, struct kvm_device_attr *attr)
{
        u8 gtod_high = 0;

        if (copy_to_user((void __user *)attr->addr, &gtod_high,
                                         sizeof(gtod_high)))
                return -EFAULT;
        VM_EVENT(kvm, 3, "QUERY: TOD extension: 0x%x", gtod_high);

        return 0;

}

static int kvm_s390_get_tod_low(struct kvm *kvm, struct kvm_device_attr *attr)
{
        u64 gtod;

        gtod = kvm_s390_get_tod_clock_fast(kvm);
        if (copy_to_user((void __user *)attr->addr, &gtod, sizeof(gtod)))
                return -EFAULT;
        VM_EVENT(kvm, 3, "QUERY: TOD base: 0x%llx", gtod);

        return 0;
}

static int kvm_s390_get_tod(struct kvm *kvm, struct kvm_device_attr *attr)
{
        int ret;

        if (attr->flags)
                return -EINVAL;

        switch (attr->attr) {
        case KVM_S390_VM_TOD_EXT:
                ret = kvm_s390_get_tod_ext(kvm, attr);
                break;
        case KVM_S390_VM_TOD_HIGH:
                ret = kvm_s390_get_tod_high(kvm, attr);
                break;
        case KVM_S390_VM_TOD_LOW:
                ret = kvm_s390_get_tod_low(kvm, attr);
                break;
        default:
                ret = -ENXIO;
                break;
        }
        return ret;
}

static int kvm_s390_set_processor(struct kvm *kvm, struct kvm_device_attr *attr)
{
        struct kvm_s390_vm_cpu_processor *proc;
        u16 lowest_ibc, unblocked_ibc;
        int ret = 0;

        mutex_lock(&kvm->lock);
        if (kvm->created_vcpus) {
                ret = -EBUSY;
                goto out;
        }
        proc = kzalloc(sizeof(*proc), GFP_KERNEL);
        if (!proc) {
                ret = -ENOMEM;
                goto out;
        }
        if (!copy_from_user(proc, (void __user *)attr->addr,
                            sizeof(*proc))) {
                kvm->arch.model.cpuid = proc->cpuid;
                lowest_ibc = sclp.ibc >> 16 & 0xfff;
                unblocked_ibc = sclp.ibc & 0xfff;
                if (lowest_ibc && proc->ibc) {
                        if (proc->ibc > unblocked_ibc)
                                kvm->arch.model.ibc = unblocked_ibc;
                        else if (proc->ibc < lowest_ibc)
                                kvm->arch.model.ibc = lowest_ibc;
                        else
                                kvm->arch.model.ibc = proc->ibc;
                }
                memcpy(kvm->arch.model.fac_list, proc->fac_list,
                       S390_ARCH_FAC_LIST_SIZE_BYTE);
                VM_EVENT(kvm, 3, "SET: guest ibc: 0x%4.4x, guest cpuid: 0x%16.16llx",
                         kvm->arch.model.ibc,
                         kvm->arch.model.cpuid);
                VM_EVENT(kvm, 3, "SET: guest faclist: 0x%16.16llx.%16.16llx.%16.16llx",
                         kvm->arch.model.fac_list[0],
                         kvm->arch.model.fac_list[1],
                         kvm->arch.model.fac_list[2]);
        } else
                ret = -EFAULT;
        kfree(proc);
out:
        mutex_unlock(&kvm->lock);
        return ret;
}

static int kvm_s390_set_processor_feat(struct kvm *kvm,
                                       struct kvm_device_attr *attr)
{
        struct kvm_s390_vm_cpu_feat data;
        int ret = -EBUSY;

        if (copy_from_user(&data, (void __user *)attr->addr, sizeof(data)))
                return -EFAULT;
        if (!bitmap_subset((unsigned long *) data.feat,
                           kvm_s390_available_cpu_feat,
                           KVM_S390_VM_CPU_FEAT_NR_BITS))
                return -EINVAL;

        mutex_lock(&kvm->lock);
        if (!atomic_read(&kvm->online_vcpus)) {
                bitmap_copy(kvm->arch.cpu_feat, (unsigned long *) data.feat,
                            KVM_S390_VM_CPU_FEAT_NR_BITS);
                ret = 0;
        }
        mutex_unlock(&kvm->lock);
        return ret;
}

static int kvm_s390_set_processor_subfunc(struct kvm *kvm,
                                          struct kvm_device_attr *attr)
{
        /*
         * Once supported by kernel + hw, we have to store the subfunctions
         * in kvm->arch and remember that user space configured them.
         */
        return -ENXIO;
}

static int kvm_s390_set_cpu_model(struct kvm *kvm, struct kvm_device_attr *attr)
{
        int ret = -ENXIO;

        switch (attr->attr) {
        case KVM_S390_VM_CPU_PROCESSOR:
                ret = kvm_s390_set_processor(kvm, attr);
                break;
        case KVM_S390_VM_CPU_PROCESSOR_FEAT:
                ret = kvm_s390_set_processor_feat(kvm, attr);
                break;
        case KVM_S390_VM_CPU_PROCESSOR_SUBFUNC:
                ret = kvm_s390_set_processor_subfunc(kvm, attr);
                break;
        }
        return ret;
}

static int kvm_s390_get_processor(struct kvm *kvm, struct kvm_device_attr *attr)
{
        struct kvm_s390_vm_cpu_processor *proc;
        int ret = 0;

        proc = kzalloc(sizeof(*proc), GFP_KERNEL);
        if (!proc) {
                ret = -ENOMEM;
                goto out;
        }
        proc->cpuid = kvm->arch.model.cpuid;
        proc->ibc = kvm->arch.model.ibc;
        memcpy(&proc->fac_list, kvm->arch.model.fac_list,
               S390_ARCH_FAC_LIST_SIZE_BYTE);
        VM_EVENT(kvm, 3, "GET: guest ibc: 0x%4.4x, guest cpuid: 0x%16.16llx",
                 kvm->arch.model.ibc,
                 kvm->arch.model.cpuid);
        VM_EVENT(kvm, 3, "GET: guest faclist: 0x%16.16llx.%16.16llx.%16.16llx",
                 kvm->arch.model.fac_list[0],
                 kvm->arch.model.fac_list[1],
                 kvm->arch.model.fac_list[2]);
        if (copy_to_user((void __user *)attr->addr, proc, sizeof(*proc)))
                ret = -EFAULT;
        kfree(proc);
out:
        return ret;
}

static int kvm_s390_get_machine(struct kvm *kvm, struct kvm_device_attr *attr)
{
        struct kvm_s390_vm_cpu_machine *mach;
        int ret = 0;

        mach = kzalloc(sizeof(*mach), GFP_KERNEL);
        if (!mach) {
                ret = -ENOMEM;
                goto out;
        }
        get_cpu_id((struct cpuid *) &mach->cpuid);
        mach->ibc = sclp.ibc;
        memcpy(&mach->fac_mask, kvm->arch.model.fac_mask,
               S390_ARCH_FAC_LIST_SIZE_BYTE);
        memcpy((unsigned long *)&mach->fac_list, S390_lowcore.stfle_fac_list,
               sizeof(S390_lowcore.stfle_fac_list));
        VM_EVENT(kvm, 3, "GET: host ibc:  0x%4.4x, host cpuid:  0x%16.16llx",
                 kvm->arch.model.ibc,
                 kvm->arch.model.cpuid);
        VM_EVENT(kvm, 3, "GET: host facmask:  0x%16.16llx.%16.16llx.%16.16llx",
                 mach->fac_mask[0],
                 mach->fac_mask[1],
                 mach->fac_mask[2]);
        VM_EVENT(kvm, 3, "GET: host faclist:  0x%16.16llx.%16.16llx.%16.16llx",
                 mach->fac_list[0],
                 mach->fac_list[1],
                 mach->fac_list[2]);
        if (copy_to_user((void __user *)attr->addr, mach, sizeof(*mach)))
                ret = -EFAULT;
        kfree(mach);
out:
        return ret;
}

static int kvm_s390_get_processor_feat(struct kvm *kvm,
                                       struct kvm_device_attr *attr)
{
        struct kvm_s390_vm_cpu_feat data;

        bitmap_copy((unsigned long *) data.feat, kvm->arch.cpu_feat,
                    KVM_S390_VM_CPU_FEAT_NR_BITS);
        if (copy_to_user((void __user *)attr->addr, &data, sizeof(data)))
                return -EFAULT;
        return 0;
}

static int kvm_s390_get_machine_feat(struct kvm *kvm,
                                     struct kvm_device_attr *attr)
{
        struct kvm_s390_vm_cpu_feat data;

        bitmap_copy((unsigned long *) data.feat,
                    kvm_s390_available_cpu_feat,
                    KVM_S390_VM_CPU_FEAT_NR_BITS);
        if (copy_to_user((void __user *)attr->addr, &data, sizeof(data)))
                return -EFAULT;
        return 0;
}

static int kvm_s390_get_processor_subfunc(struct kvm *kvm,
                                          struct kvm_device_attr *attr)
{
        /*
         * Once we can actually configure subfunctions (kernel + hw support),
         * we have to check if they were already set by user space, if so copy
         * them from kvm->arch.
         */
        return -ENXIO;
}

static int kvm_s390_get_machine_subfunc(struct kvm *kvm,
                                        struct kvm_device_attr *attr)
{
        if (copy_to_user((void __user *)attr->addr, &kvm_s390_available_subfunc,
            sizeof(struct kvm_s390_vm_cpu_subfunc)))
                return -EFAULT;
        return 0;
}
static int kvm_s390_get_cpu_model(struct kvm *kvm, struct kvm_device_attr *attr)
{
        int ret = -ENXIO;

        switch (attr->attr) {
        case KVM_S390_VM_CPU_PROCESSOR:
                ret = kvm_s390_get_processor(kvm, attr);
                break;
        case KVM_S390_VM_CPU_MACHINE:
                ret = kvm_s390_get_machine(kvm, attr);
                break;
        case KVM_S390_VM_CPU_PROCESSOR_FEAT:
                ret = kvm_s390_get_processor_feat(kvm, attr);
                break;
        case KVM_S390_VM_CPU_MACHINE_FEAT:
                ret = kvm_s390_get_machine_feat(kvm, attr);
                break;
        case KVM_S390_VM_CPU_PROCESSOR_SUBFUNC:
                ret = kvm_s390_get_processor_subfunc(kvm, attr);
                break;
        case KVM_S390_VM_CPU_MACHINE_SUBFUNC:
                ret = kvm_s390_get_machine_subfunc(kvm, attr);
                break;
        }
        return ret;
}

static int kvm_s390_vm_set_attr(struct kvm *kvm, struct kvm_device_attr *attr)
{
        int ret;

        switch (attr->group) {
        case KVM_S390_VM_MEM_CTRL:
                ret = kvm_s390_set_mem_control(kvm, attr);
                break;
        case KVM_S390_VM_TOD:
                ret = kvm_s390_set_tod(kvm, attr);
                break;
        case KVM_S390_VM_CPU_MODEL:
                ret = kvm_s390_set_cpu_model(kvm, attr);
                break;
        case KVM_S390_VM_CRYPTO:
                ret = kvm_s390_vm_set_crypto(kvm, attr);
                break;
        case KVM_S390_VM_MIGRATION:
                ret = kvm_s390_vm_set_migration(kvm, attr);
                break;
        default:
                ret = -ENXIO;
                break;
        }

        return ret;
}

static int kvm_s390_vm_get_attr(struct kvm *kvm, struct kvm_device_attr *attr)
{
        int ret;

        switch (attr->group) {
        case KVM_S390_VM_MEM_CTRL:
                ret = kvm_s390_get_mem_control(kvm, attr);
                break;
        case KVM_S390_VM_TOD:
                ret = kvm_s390_get_tod(kvm, attr);
                break;
        case KVM_S390_VM_CPU_MODEL:
                ret = kvm_s390_get_cpu_model(kvm, attr);
                break;
        case KVM_S390_VM_MIGRATION:
                ret = kvm_s390_vm_get_migration(kvm, attr);
                break;
        default:
                ret = -ENXIO;
                break;
        }

        return ret;
}

static int kvm_s390_vm_has_attr(struct kvm *kvm, struct kvm_device_attr *attr)
{
        int ret;

        switch (attr->group) {
        case KVM_S390_VM_MEM_CTRL:
                switch (attr->attr) {
                case KVM_S390_VM_MEM_ENABLE_CMMA:
                case KVM_S390_VM_MEM_CLR_CMMA:
                        ret = sclp.has_cmma ? 0 : -ENXIO;
                        break;
                case KVM_S390_VM_MEM_LIMIT_SIZE:
                        ret = 0;
                        break;
                default:
                        ret = -ENXIO;
                        break;
                }
                break;
        case KVM_S390_VM_TOD:
                switch (attr->attr) {
                case KVM_S390_VM_TOD_LOW:
                case KVM_S390_VM_TOD_HIGH:
                        ret = 0;
                        break;
                default:
                        ret = -ENXIO;
                        break;
                }
                break;
        case KVM_S390_VM_CPU_MODEL:
                switch (attr->attr) {
                case KVM_S390_VM_CPU_PROCESSOR:
                case KVM_S390_VM_CPU_MACHINE:
                case KVM_S390_VM_CPU_PROCESSOR_FEAT:
                case KVM_S390_VM_CPU_MACHINE_FEAT:
                case KVM_S390_VM_CPU_MACHINE_SUBFUNC:
                        ret = 0;
                        break;
                /* configuring subfunctions is not supported yet */
                case KVM_S390_VM_CPU_PROCESSOR_SUBFUNC:
                default:
                        ret = -ENXIO;
                        break;
                }
                break;
        case KVM_S390_VM_CRYPTO:
                switch (attr->attr) {
                case KVM_S390_VM_CRYPTO_ENABLE_AES_KW:
                case KVM_S390_VM_CRYPTO_ENABLE_DEA_KW:
                case KVM_S390_VM_CRYPTO_DISABLE_AES_KW:
                case KVM_S390_VM_CRYPTO_DISABLE_DEA_KW:
                        ret = 0;
                        break;
                default:
                        ret = -ENXIO;
                        break;
                }
                break;
        case KVM_S390_VM_MIGRATION:
                ret = 0;
                break;
        default:
                ret = -ENXIO;
                break;
        }

        return ret;
}

static long kvm_s390_get_skeys(struct kvm *kvm, struct kvm_s390_skeys *args)
{
        uint8_t *keys;
        uint64_t hva;
        int srcu_idx, i, r = 0;

        if (args->flags != 0)
                return -EINVAL;

        /* Is this guest using storage keys? */
        if (!mm_use_skey(current->mm))
                return KVM_S390_GET_SKEYS_NONE;

        /* Enforce sane limit on memory allocation */
        if (args->count < 1 || args->count > KVM_S390_SKEYS_MAX)
                return -EINVAL;

        keys = kvmalloc_array(args->count, sizeof(uint8_t), GFP_KERNEL);
        if (!keys)
                return -ENOMEM;

        down_read(&current->mm->mmap_sem);
        srcu_idx = srcu_read_lock(&kvm->srcu);
        for (i = 0; i < args->count; i++) {
                hva = gfn_to_hva(kvm, args->start_gfn + i);
                if (kvm_is_error_hva(hva)) {
                        r = -EFAULT;
                        break;
                }

                r = get_guest_storage_key(current->mm, hva, &keys[i]);
                if (r)
                        break;
        }
        srcu_read_unlock(&kvm->srcu, srcu_idx);
        up_read(&current->mm->mmap_sem);

        if (!r) {
                r = copy_to_user((uint8_t __user *)args->skeydata_addr, keys,
                                 sizeof(uint8_t) * args->count);
                if (r)
                        r = -EFAULT;
        }

        kvfree(keys);
        return r;
}

static long kvm_s390_set_skeys(struct kvm *kvm, struct kvm_s390_skeys *args)
{
        uint8_t *keys;
        uint64_t hva;
        int srcu_idx, i, r = 0;

        if (args->flags != 0)
                return -EINVAL;

        /* Enforce sane limit on memory allocation */
        if (args->count < 1 || args->count > KVM_S390_SKEYS_MAX)
                return -EINVAL;

        keys = kvmalloc_array(args->count, sizeof(uint8_t), GFP_KERNEL);
        if (!keys)
                return -ENOMEM;

        r = copy_from_user(keys, (uint8_t __user *)args->skeydata_addr,
                           sizeof(uint8_t) * args->count);
        if (r) {
                r = -EFAULT;
                goto out;
        }

        /* Enable storage key handling for the guest */
        r = s390_enable_skey();
        if (r)
                goto out;

        down_read(&current->mm->mmap_sem);
        srcu_idx = srcu_read_lock(&kvm->srcu);
        for (i = 0; i < args->count; i++) {
                hva = gfn_to_hva(kvm, args->start_gfn + i);
                if (kvm_is_error_hva(hva)) {
                        r = -EFAULT;
                        break;
                }

                /* Lowest order bit is reserved */
                if (keys[i] & 0x01) {
                        r = -EINVAL;
                        break;
                }

                r = set_guest_storage_key(current->mm, hva, keys[i], 0);
                if (r)
                        break;
        }
        srcu_read_unlock(&kvm->srcu, srcu_idx);
        up_read(&current->mm->mmap_sem);
out:
        kvfree(keys);
        return r;
}

/*
 * Base address and length must be sent at the start of each block, therefore
 * it's cheaper to send some clean data, as long as it's less than the size of
 * two longs.
 */
#define KVM_S390_MAX_BIT_DISTANCE (2 * sizeof(void *))
/* for consistency */
#define KVM_S390_CMMA_SIZE_MAX ((u32)KVM_S390_SKEYS_MAX)

/*
 * This function searches for the next page with dirty CMMA attributes, and
 * saves the attributes in the buffer up to either the end of the buffer or
 * until a block of at least KVM_S390_MAX_BIT_DISTANCE clean bits is found;
 * no trailing clean bytes are saved.
 * In case no dirty bits were found, or if CMMA was not enabled or used, the
 * output buffer will indicate 0 as length.
 */
static int kvm_s390_get_cmma_bits(struct kvm *kvm,
                                  struct kvm_s390_cmma_log *args)
{
        struct kvm_s390_migration_state *s = kvm->arch.migration_state;
        unsigned long bufsize, hva, pgstev, i, next, cur;
        int srcu_idx, peek, r = 0, rr;
        u8 *res;

        cur = args->start_gfn;
        i = next = pgstev = 0;

        if (unlikely(!kvm->arch.use_cmma))
                return -ENXIO;
        /* Invalid/unsupported flags were specified */
        if (args->flags & ~KVM_S390_CMMA_PEEK)
                return -EINVAL;
        /* Migration mode query, and we are not doing a migration */
        peek = !!(args->flags & KVM_S390_CMMA_PEEK);
        if (!peek && !s)
                return -EINVAL;
        /* CMMA is disabled or was not used, or the buffer has length zero */
        bufsize = min(args->count, KVM_S390_CMMA_SIZE_MAX);
        if (!bufsize || !kvm->mm->context.use_cmma) {
                memset(args, 0, sizeof(*args));
                return 0;
        }

        if (!peek) {
                /* We are not peeking, and there are no dirty pages */
                if (!atomic64_read(&s->dirty_pages)) {
                        memset(args, 0, sizeof(*args));
                        return 0;
                }
                cur = find_next_bit(s->pgste_bitmap, s->bitmap_size,
                                    args->start_gfn);
                if (cur >= s->bitmap_size)      /* nothing found, loop back */
                        cur = find_next_bit(s->pgste_bitmap, s->bitmap_size, 0);
                if (cur >= s->bitmap_size) {    /* again! (very unlikely) */
                        memset(args, 0, sizeof(*args));
                        return 0;
                }
                next = find_next_bit(s->pgste_bitmap, s->bitmap_size, cur + 1);
        }

        res = vmalloc(bufsize);
        if (!res)
                return -ENOMEM;

        args->start_gfn = cur;

        down_read(&kvm->mm->mmap_sem);
        srcu_idx = srcu_read_lock(&kvm->srcu);
        while (i < bufsize) {
                hva = gfn_to_hva(kvm, cur);
                if (kvm_is_error_hva(hva)) {
                        r = -EFAULT;
                        break;
                }
                /* decrement only if we actually flipped the bit to 0 */
                if (!peek && test_and_clear_bit(cur, s->pgste_bitmap))
                        atomic64_dec(&s->dirty_pages);
                r = get_pgste(kvm->mm, hva, &pgstev);
                if (r < 0)
                        pgstev = 0;
                /* save the value */
                res[i++] = (pgstev >> 24) & 0x43;
                /*
                 * if the next bit is too far away, stop.
                 * if we reached the previous "next", find the next one
                 */
                if (!peek) {
                        if (next > cur + KVM_S390_MAX_BIT_DISTANCE)
                                break;
                        if (cur == next)
                                next = find_next_bit(s->pgste_bitmap,
                                                     s->bitmap_size, cur + 1);
                /* reached the end of the bitmap or of the buffer, stop */
                        if ((next >= s->bitmap_size) ||
                            (next >= args->start_gfn + bufsize))
                                break;
                }
                cur++;
        }
        srcu_read_unlock(&kvm->srcu, srcu_idx);
        up_read(&kvm->mm->mmap_sem);
        args->count = i;
        args->remaining = s ? atomic64_read(&s->dirty_pages) : 0;

        rr = copy_to_user((void __user *)args->values, res, args->count);
        if (rr)
                r = -EFAULT;

        vfree(res);
        return r;
}

/*
 * This function sets the CMMA attributes for the given pages. If the input
 * buffer has zero length, no action is taken, otherwise the attributes are
 * set and the mm->context.use_cmma flag is set.
 */
static int kvm_s390_set_cmma_bits(struct kvm *kvm,
                                  const struct kvm_s390_cmma_log *args)
{
        unsigned long hva, mask, pgstev, i;
        uint8_t *bits;
        int srcu_idx, r = 0;

        mask = args->mask;

        if (!kvm->arch.use_cmma)
                return -ENXIO;
        /* invalid/unsupported flags */
        if (args->flags != 0)
                return -EINVAL;
        /* Enforce sane limit on memory allocation */
        if (args->count > KVM_S390_CMMA_SIZE_MAX)
                return -EINVAL;
        /* Nothing to do */
        if (args->count == 0)
                return 0;

        bits = vmalloc(sizeof(*bits) * args->count);
        if (!bits)
                return -ENOMEM;

        r = copy_from_user(bits, (void __user *)args->values, args->count);
        if (r) {
                r = -EFAULT;
                goto out;
        }

        down_read(&kvm->mm->mmap_sem);
        srcu_idx = srcu_read_lock(&kvm->srcu);
        for (i = 0; i < args->count; i++) {
                hva = gfn_to_hva(kvm, args->start_gfn + i);
                if (kvm_is_error_hva(hva)) {
                        r = -EFAULT;
                        break;
                }

                pgstev = bits[i];
                pgstev = pgstev << 24;
                mask &= _PGSTE_GPS_USAGE_MASK | _PGSTE_GPS_NODAT;
                set_pgste_bits(kvm->mm, hva, mask, pgstev);
        }
        srcu_read_unlock(&kvm->srcu, srcu_idx);
        up_read(&kvm->mm->mmap_sem);

        if (!kvm->mm->context.use_cmma) {
                down_write(&kvm->mm->mmap_sem);
                kvm->mm->context.use_cmma = 1;
                up_write(&kvm->mm->mmap_sem);
        }
out:
        vfree(bits);
        return r;
}

long kvm_arch_vm_ioctl(struct file *filp,
                       unsigned int ioctl, unsigned long arg)
{
        struct kvm *kvm = filp->private_data;
        void __user *argp = (void __user *)arg;
        struct kvm_device_attr attr;
        int r;

        switch (ioctl) {
        case KVM_S390_INTERRUPT: {
                struct kvm_s390_interrupt s390int;

                r = -EFAULT;
                if (copy_from_user(&s390int, argp, sizeof(s390int)))
                        break;
                r = kvm_s390_inject_vm(kvm, &s390int);
                break;
        }
        case KVM_ENABLE_CAP: {
                struct kvm_enable_cap cap;
                r = -EFAULT;
                if (copy_from_user(&cap, argp, sizeof(cap)))
                        break;
                r = kvm_vm_ioctl_enable_cap(kvm, &cap);
                break;
        }
        case KVM_CREATE_IRQCHIP: {
                struct kvm_irq_routing_entry routing;

                r = -EINVAL;
                if (kvm->arch.use_irqchip) {
                        /* Set up dummy routing. */
                        memset(&routing, 0, sizeof(routing));
                        r = kvm_set_irq_routing(kvm, &routing, 0, 0);
                }
                break;
        }
        case KVM_SET_DEVICE_ATTR: {
                r = -EFAULT;
                if (copy_from_user(&attr, (void __user *)arg, sizeof(attr)))
                        break;
                r = kvm_s390_vm_set_attr(kvm, &attr);
                break;
        }
        case KVM_GET_DEVICE_ATTR: {
                r = -EFAULT;
                if (copy_from_user(&attr, (void __user *)arg, sizeof(attr)))
                        break;
                r = kvm_s390_vm_get_attr(kvm, &attr);
                break;
        }
        case KVM_HAS_DEVICE_ATTR: {
                r = -EFAULT;
                if (copy_from_user(&attr, (void __user *)arg, sizeof(attr)))
                        break;
                r = kvm_s390_vm_has_attr(kvm, &attr);
                break;
        }
        case KVM_S390_GET_SKEYS: {
                struct kvm_s390_skeys args;

                r = -EFAULT;
                if (copy_from_user(&args, argp,
                                   sizeof(struct kvm_s390_skeys)))
                        break;
                r = kvm_s390_get_skeys(kvm, &args);
                break;
        }
        case KVM_S390_SET_SKEYS: {
                struct kvm_s390_skeys args;

                r = -EFAULT;
                if (copy_from_user(&args, argp,
                                   sizeof(struct kvm_s390_skeys)))
                        break;
                r = kvm_s390_set_skeys(kvm, &args);
                break;
        }
        case KVM_S390_GET_CMMA_BITS: {
                struct kvm_s390_cmma_log args;

                r = -EFAULT;
                if (copy_from_user(&args, argp, sizeof(args)))
                        break;
                r = kvm_s390_get_cmma_bits(kvm, &args);
                if (!r) {
                        r = copy_to_user(argp, &args, sizeof(args));
                        if (r)
                                r = -EFAULT;
                }
                break;
        }
        case KVM_S390_SET_CMMA_BITS: {
                struct kvm_s390_cmma_log args;

                r = -EFAULT;
                if (copy_from_user(&args, argp, sizeof(args)))
                        break;
                r = kvm_s390_set_cmma_bits(kvm, &args);
                break;
        }
        default:
                r = -ENOTTY;
        }

        return r;
}

static int kvm_s390_query_ap_config(u8 *config)
{
        u32 fcn_code = 0x04000000UL;
        u32 cc = 0;

        memset(config, 0, 128);
        asm volatile(
                "lgr 0,%1\n"
                "lgr 2,%2\n"
                ".long 0xb2af0000\n"            /* PQAP(QCI) */
                "0: ipm %0\n"
                "srl %0,28\n"
                "1:\n"
                EX_TABLE(0b, 1b)
                : "+r" (cc)
                : "r" (fcn_code), "r" (config)
                : "cc", "0", "2", "memory"
        );

        return cc;
}

static int kvm_s390_apxa_installed(void)
{
        u8 config[128];
        int cc;

        if (test_facility(12)) {
                cc = kvm_s390_query_ap_config(config);

                if (cc)
                        pr_err("PQAP(QCI) failed with cc=%d", cc);
                else
                        return config[0] & 0x40;
        }

        return 0;
}

static void kvm_s390_set_crycb_format(struct kvm *kvm)
{
        kvm->arch.crypto.crycbd = (__u32)(unsigned long) kvm->arch.crypto.crycb;

        if (kvm_s390_apxa_installed())
                kvm->arch.crypto.crycbd |= CRYCB_FORMAT2;
        else
                kvm->arch.crypto.crycbd |= CRYCB_FORMAT1;
}

static u64 kvm_s390_get_initial_cpuid(void)
{
        struct cpuid cpuid;

        get_cpu_id(&cpuid);
        cpuid.version = 0xff;
        return *((u64 *) &cpuid);
}

static void kvm_s390_crypto_init(struct kvm *kvm)
{
        if (!test_kvm_facility(kvm, 76))
                return;

        kvm->arch.crypto.crycb = &kvm->arch.sie_page2->crycb;
        kvm_s390_set_crycb_format(kvm);

        /* Enable AES/DEA protected key functions by default */
        kvm->arch.crypto.aes_kw = 1;
        kvm->arch.crypto.dea_kw = 1;
        get_random_bytes(kvm->arch.crypto.crycb->aes_wrapping_key_mask,
                         sizeof(kvm->arch.crypto.crycb->aes_wrapping_key_mask));
        get_random_bytes(kvm->arch.crypto.crycb->dea_wrapping_key_mask,
                         sizeof(kvm->arch.crypto.crycb->dea_wrapping_key_mask));
}

static void sca_dispose(struct kvm *kvm)
{
        if (kvm->arch.use_esca)
                free_pages_exact(kvm->arch.sca, sizeof(struct esca_block));
        else
                free_page((unsigned long)(kvm->arch.sca));
        kvm->arch.sca = NULL;
}

int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
{
        gfp_t alloc_flags = GFP_KERNEL;
        int i, rc;
        char debug_name[16];
        static unsigned long sca_offset;

        rc = -EINVAL;
#ifdef CONFIG_KVM_S390_UCONTROL
        if (type & ~KVM_VM_S390_UCONTROL)
                goto out_err;
        if ((type & KVM_VM_S390_UCONTROL) && (!capable(CAP_SYS_ADMIN)))
                goto out_err;
#else
        if (type)
                goto out_err;
#endif

        rc = s390_enable_sie();
        if (rc)
                goto out_err;

        rc = -ENOMEM;

        ratelimit_state_init(&kvm->arch.sthyi_limit, 5 * HZ, 500);

        kvm->arch.use_esca = 0; /* start with basic SCA */
        if (!sclp.has_64bscao)
                alloc_flags |= GFP_DMA;
        rwlock_init(&kvm->arch.sca_lock);
        kvm->arch.sca = (struct bsca_block *) get_zeroed_page(alloc_flags);
        if (!kvm->arch.sca)
                goto out_err;
        spin_lock(&kvm_lock);
        sca_offset += 16;
        if (sca_offset + sizeof(struct bsca_block) > PAGE_SIZE)
                sca_offset = 0;
        kvm->arch.sca = (struct bsca_block *)
                        ((char *) kvm->arch.sca + sca_offset);
        spin_unlock(&kvm_lock);

        sprintf(debug_name, "kvm-%u", current->pid);

        kvm->arch.dbf = debug_register(debug_name, 32, 1, 7 * sizeof(long));
        if (!kvm->arch.dbf)
                goto out_err;

        kvm->arch.sie_page2 =
             (struct sie_page2 *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
        if (!kvm->arch.sie_page2)
                goto out_err;

        /* Populate the facility mask initially. */
        memcpy(kvm->arch.model.fac_mask, S390_lowcore.stfle_fac_list,
               sizeof(S390_lowcore.stfle_fac_list));
        for (i = 0; i < S390_ARCH_FAC_LIST_SIZE_U64; i++) {
                if (i < kvm_s390_fac_list_mask_size())
                        kvm->arch.model.fac_mask[i] &= kvm_s390_fac_list_mask[i];
                else
                        kvm->arch.model.fac_mask[i] = 0UL;
        }

        /* Populate the facility list initially. */
        kvm->arch.model.fac_list = kvm->arch.sie_page2->fac_list;
        memcpy(kvm->arch.model.fac_list, kvm->arch.model.fac_mask,
               S390_ARCH_FAC_LIST_SIZE_BYTE);

        /* we are always in czam mode - even on pre z14 machines */
        set_kvm_facility(kvm->arch.model.fac_mask, 138);
        set_kvm_facility(kvm->arch.model.fac_list, 138);
        /* we emulate STHYI in kvm */
        set_kvm_facility(kvm->arch.model.fac_mask, 74);
        set_kvm_facility(kvm->arch.model.fac_list, 74);
        if (MACHINE_HAS_TLB_GUEST) {
                set_kvm_facility(kvm->arch.model.fac_mask, 147);
                set_kvm_facility(kvm->arch.model.fac_list, 147);
        }

        kvm->arch.model.cpuid = kvm_s390_get_initial_cpuid();
        kvm->arch.model.ibc = sclp.ibc & 0x0fff;

        kvm_s390_crypto_init(kvm);

        mutex_init(&kvm->arch.float_int.ais_lock);
        kvm->arch.float_int.simm = 0;
        kvm->arch.float_int.nimm = 0;
        spin_lock_init(&kvm->arch.float_int.lock);
        for (i = 0; i < FIRQ_LIST_COUNT; i++)
                INIT_LIST_HEAD(&kvm->arch.float_int.lists[i]);
        init_waitqueue_head(&kvm->arch.ipte_wq);
        mutex_init(&kvm->arch.ipte_mutex);

        debug_register_view(kvm->arch.dbf, &debug_sprintf_view);
        VM_EVENT(kvm, 3, "vm created with type %lu", type);

        if (type & KVM_VM_S390_UCONTROL) {
                kvm->arch.gmap = NULL;
                kvm->arch.mem_limit = KVM_S390_NO_MEM_LIMIT;
        } else {
                if (sclp.hamax == U64_MAX)
                        kvm->arch.mem_limit = TASK_SIZE_MAX;
                else
                        kvm->arch.mem_limit = min_t(unsigned long, TASK_SIZE_MAX,
                                                    sclp.hamax + 1);
                kvm->arch.gmap = gmap_create(current->mm, kvm->arch.mem_limit - 1);
                if (!kvm->arch.gmap)
                        goto out_err;
                kvm->arch.gmap->private = kvm;
                kvm->arch.gmap->pfault_enabled = 0;
        }

        kvm->arch.css_support = 0;
        kvm->arch.use_irqchip = 0;
        kvm->arch.epoch = 0;

        spin_lock_init(&kvm->arch.start_stop_lock);
        kvm_s390_vsie_init(kvm);
        KVM_EVENT(3, "vm 0x%pK created by pid %u", kvm, current->pid);

        return 0;
out_err:
        free_page((unsigned long)kvm->arch.sie_page2);
        debug_unregister(kvm->arch.dbf);
        sca_dispose(kvm);
        KVM_EVENT(3, "creation of vm failed: %d", rc);
        return rc;
}

bool kvm_arch_has_vcpu_debugfs(void)
{
        return false;
}

int kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
{
        return 0;
}

void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
{
        VCPU_EVENT(vcpu, 3, "%s", "free cpu");
        trace_kvm_s390_destroy_vcpu(vcpu->vcpu_id);
        kvm_s390_clear_local_irqs(vcpu);
        kvm_clear_async_pf_completion_queue(vcpu);
        if (!kvm_is_ucontrol(vcpu->kvm))
                sca_del_vcpu(vcpu);

        if (kvm_is_ucontrol(vcpu->kvm))
                gmap_remove(vcpu->arch.gmap);

        if (vcpu->kvm->arch.use_cmma)
                kvm_s390_vcpu_unsetup_cmma(vcpu);
        free_page((unsigned long)(vcpu->arch.sie_block));

        kvm_vcpu_uninit(vcpu);
        kmem_cache_free(kvm_vcpu_cache, vcpu);
}

static void kvm_free_vcpus(struct kvm *kvm)
{
        unsigned int i;
        struct kvm_vcpu *vcpu;

        kvm_for_each_vcpu(i, vcpu, kvm)
                kvm_arch_vcpu_destroy(vcpu);

        mutex_lock(&kvm->lock);
        for (i = 0; i < atomic_read(&kvm->online_vcpus); i++)
                kvm->vcpus[i] = NULL;

        atomic_set(&kvm->online_vcpus, 0);
        mutex_unlock(&kvm->lock);
}

void kvm_arch_destroy_vm(struct kvm *kvm)
{
        kvm_free_vcpus(kvm);
        sca_dispose(kvm);
        debug_unregister(kvm->arch.dbf);
        free_page((unsigned long)kvm->arch.sie_page2);
        if (!kvm_is_ucontrol(kvm))
                gmap_remove(kvm->arch.gmap);
        kvm_s390_destroy_adapters(kvm);
        kvm_s390_clear_float_irqs(kvm);
        kvm_s390_vsie_destroy(kvm);
        if (kvm->arch.migration_state) {
                vfree(kvm->arch.migration_state->pgste_bitmap);
                kfree(kvm->arch.migration_state);
        }
        KVM_EVENT(3, "vm 0x%pK destroyed", kvm);
}

/* Section: vcpu related */
static int __kvm_ucontrol_vcpu_init(struct kvm_vcpu *vcpu)
{
        vcpu->arch.gmap = gmap_create(current->mm, -1UL);
        if (!vcpu->arch.gmap)
                return -ENOMEM;
        vcpu->arch.gmap->private = vcpu->kvm;

        return 0;
}

static void sca_del_vcpu(struct kvm_vcpu *vcpu)
{
        if (!kvm_s390_use_sca_entries())
                return;
        read_lock(&vcpu->kvm->arch.sca_lock);
        if (vcpu->kvm->arch.use_esca) {
                struct esca_block *sca = vcpu->kvm->arch.sca;

                clear_bit_inv(vcpu->vcpu_id, (unsigned long *) sca->mcn);
                sca->cpu[vcpu->vcpu_id].sda = 0;
        } else {
                struct bsca_block *sca = vcpu->kvm->arch.sca;

                clear_bit_inv(vcpu->vcpu_id, (unsigned long *) &sca->mcn);
                sca->cpu[vcpu->vcpu_id].sda = 0;
        }
        read_unlock(&vcpu->kvm->arch.sca_lock);
}

static void sca_add_vcpu(struct kvm_vcpu *vcpu)
{
        if (!kvm_s390_use_sca_entries()) {
                struct bsca_block *sca = vcpu->kvm->arch.sca;

                /* we still need the basic sca for the ipte control */
                vcpu->arch.sie_block->scaoh = (__u32)(((__u64)sca) >> 32);
                vcpu->arch.sie_block->scaol = (__u32)(__u64)sca;
        }
        read_lock(&vcpu->kvm->arch.sca_lock);
        if (vcpu->kvm->arch.use_esca) {
                struct esca_block *sca = vcpu->kvm->arch.sca;

                sca->cpu[vcpu->vcpu_id].sda = (__u64) vcpu->arch.sie_block;
                vcpu->arch.sie_block->scaoh = (__u32)(((__u64)sca) >> 32);
                vcpu->arch.sie_block->scaol = (__u32)(__u64)sca & ~0x3fU;
                vcpu->arch.sie_block->ecb2 |= ECB2_ESCA;
                set_bit_inv(vcpu->vcpu_id, (unsigned long *) sca->mcn);
        } else {
                struct bsca_block *sca = vcpu->kvm->arch.sca;

                sca->cpu[vcpu->vcpu_id].sda = (__u64) vcpu->arch.sie_block;
                vcpu->arch.sie_block->scaoh = (__u32)(((__u64)sca) >> 32);
                vcpu->arch.sie_block->scaol = (__u32)(__u64)sca;
                set_bit_inv(vcpu->vcpu_id, (unsigned long *) &sca->mcn);
        }
        read_unlock(&vcpu->kvm->arch.sca_lock);
}

/* Basic SCA to Extended SCA data copy routines */
static inline void sca_copy_entry(struct esca_entry *d, struct bsca_entry *s)
{
        d->sda = s->sda;
        d->sigp_ctrl.c = s->sigp_ctrl.c;
        d->sigp_ctrl.scn = s->sigp_ctrl.scn;
}

static void sca_copy_b_to_e(struct esca_block *d, struct bsca_block *s)
{
        int i;

        d->ipte_control = s->ipte_control;
        d->mcn[0] = s->mcn;
        for (i = 0; i < KVM_S390_BSCA_CPU_SLOTS; i++)
                sca_copy_entry(&d->cpu[i], &s->cpu[i]);
}

static int sca_switch_to_extended(struct kvm *kvm)
{
        struct bsca_block *old_sca = kvm->arch.sca;
        struct esca_block *new_sca;
        struct kvm_vcpu *vcpu;
        unsigned int vcpu_idx;
        u32 scaol, scaoh;

        new_sca = alloc_pages_exact(sizeof(*new_sca), GFP_KERNEL|__GFP_ZERO);
        if (!new_sca)
                return -ENOMEM;

        scaoh = (u32)((u64)(new_sca) >> 32);
        scaol = (u32)(u64)(new_sca) & ~0x3fU;

        kvm_s390_vcpu_block_all(kvm);
        write_lock(&kvm->arch.sca_lock);

        sca_copy_b_to_e(new_sca, old_sca);

        kvm_for_each_vcpu(vcpu_idx, vcpu, kvm) {
                vcpu->arch.sie_block->scaoh = scaoh;
                vcpu->arch.sie_block->scaol = scaol;
                vcpu->arch.sie_block->ecb2 |= ECB2_ESCA;
        }
        kvm->arch.sca = new_sca;
        kvm->arch.use_esca = 1;

        write_unlock(&kvm->arch.sca_lock);
        kvm_s390_vcpu_unblock_all(kvm);

        free_page((unsigned long)old_sca);

        VM_EVENT(kvm, 2, "Switched to ESCA (0x%pK -> 0x%pK)",
                 old_sca, kvm->arch.sca);
        return 0;
}

static int sca_can_add_vcpu(struct kvm *kvm, unsigned int id)
{
        int rc;

        if (!kvm_s390_use_sca_entries()) {
                if (id < KVM_MAX_VCPUS)
                        return true;
                return false;
        }
        if (id < KVM_S390_BSCA_CPU_SLOTS)
                return true;
        if (!sclp.has_esca || !sclp.has_64bscao)
                return false;

        mutex_lock(&kvm->lock);
        rc = kvm->arch.use_esca ? 0 : sca_switch_to_extended(kvm);
        mutex_unlock(&kvm->lock);

        return rc == 0 && id < KVM_S390_ESCA_CPU_SLOTS;
}

int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
{
        vcpu->arch.pfault_token = KVM_S390_PFAULT_TOKEN_INVALID;
        kvm_clear_async_pf_completion_queue(vcpu);
        vcpu->run->kvm_valid_regs = KVM_SYNC_PREFIX |
                                    KVM_SYNC_GPRS |
                                    KVM_SYNC_ACRS |
                                    KVM_SYNC_CRS |
                                    KVM_SYNC_ARCH0 |
                                    KVM_SYNC_PFAULT;
        kvm_s390_set_prefix(vcpu, 0);
        if (test_kvm_facility(vcpu->kvm, 64))
                vcpu->run->kvm_valid_regs |= KVM_SYNC_RICCB;
        if (test_kvm_facility(vcpu->kvm, 133))
                vcpu->run->kvm_valid_regs |= KVM_SYNC_GSCB;
        /* fprs can be synchronized via vrs, even if the guest has no vx. With
         * MACHINE_HAS_VX, (load|store)_fpu_regs() will work with vrs format.
         */
        if (MACHINE_HAS_VX)
                vcpu->run->kvm_valid_regs |= KVM_SYNC_VRS;
        else
                vcpu->run->kvm_valid_regs |= KVM_SYNC_FPRS;

        if (kvm_is_ucontrol(vcpu->kvm))
                return __kvm_ucontrol_vcpu_init(vcpu);

        return 0;
}

/* needs disabled preemption to protect from TOD sync and vcpu_load/put */
static void __start_cpu_timer_accounting(struct kvm_vcpu *vcpu)
{
        WARN_ON_ONCE(vcpu->arch.cputm_start != 0);
        raw_write_seqcount_begin(&vcpu->arch.cputm_seqcount);
        vcpu->arch.cputm_start = get_tod_clock_fast();
        raw_write_seqcount_end(&vcpu->arch.cputm_seqcount);
}

/* needs disabled preemption to protect from TOD sync and vcpu_load/put */
static void __stop_cpu_timer_accounting(struct kvm_vcpu *vcpu)
{
        WARN_ON_ONCE(vcpu->arch.cputm_start == 0);
        raw_write_seqcount_begin(&vcpu->arch.cputm_seqcount);
        vcpu->arch.sie_block->cputm -= get_tod_clock_fast() - vcpu->arch.cputm_start;
        vcpu->arch.cputm_start = 0;
        raw_write_seqcount_end(&vcpu->arch.cputm_seqcount);
}

/* needs disabled preemption to protect from TOD sync and vcpu_load/put */
static void __enable_cpu_timer_accounting(struct kvm_vcpu *vcpu)
{
        WARN_ON_ONCE(vcpu->arch.cputm_enabled);
        vcpu->arch.cputm_enabled = true;
        __start_cpu_timer_accounting(vcpu);
}

/* needs disabled preemption to protect from TOD sync and vcpu_load/put */
static void __disable_cpu_timer_accounting(struct kvm_vcpu *vcpu)
{
        WARN_ON_ONCE(!vcpu->arch.cputm_enabled);
        __stop_cpu_timer_accounting(vcpu);
        vcpu->arch.cputm_enabled = false;
}

static void enable_cpu_timer_accounting(struct kvm_vcpu *vcpu)
{
        preempt_disable(); /* protect from TOD sync and vcpu_load/put */
        __enable_cpu_timer_accounting(vcpu);
        preempt_enable();
}

static void disable_cpu_timer_accounting(struct kvm_vcpu *vcpu)
{
        preempt_disable(); /* protect from TOD sync and vcpu_load/put */
        __disable_cpu_timer_accounting(vcpu);
        preempt_enable();
}

/* set the cpu timer - may only be called from the VCPU thread itself */
void kvm_s390_set_cpu_timer(struct kvm_vcpu *vcpu, __u64 cputm)
{
        preempt_disable(); /* protect from TOD sync and vcpu_load/put */
        raw_write_seqcount_begin(&vcpu->arch.cputm_seqcount);
        if (vcpu->arch.cputm_enabled)
                vcpu->arch.cputm_start = get_tod_clock_fast();
        vcpu->arch.sie_block->cputm = cputm;
        raw_write_seqcount_end(&vcpu->arch.cputm_seqcount);
        preempt_enable();
}

/* update and get the cpu timer - can also be called from other VCPU threads */
__u64 kvm_s390_get_cpu_timer(struct kvm_vcpu *vcpu)
{
        unsigned int seq;
        __u64 value;

        if (unlikely(!vcpu->arch.cputm_enabled))
                return vcpu->arch.sie_block->cputm;

        preempt_disable(); /* protect from TOD sync and vcpu_load/put */
        do {
                seq = raw_read_seqcount(&vcpu->arch.cputm_seqcount);
                /*
                 * If the writer would ever execute a read in the critical
                 * section, e.g. in irq context, we have a deadlock.
                 */
                WARN_ON_ONCE((seq & 1) && smp_processor_id() == vcpu->cpu);
                value = vcpu->arch.sie_block->cputm;
                /* if cputm_start is 0, accounting is being started/stopped */
                if (likely(vcpu->arch.cputm_start))
                        value -= get_tod_clock_fast() - vcpu->arch.cputm_start;
        } while (read_seqcount_retry(&vcpu->arch.cputm_seqcount, seq & ~1));
        preempt_enable();
        return value;
}

void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
{

        gmap_enable(vcpu->arch.enabled_gmap);
        atomic_or(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags);
        if (vcpu->arch.cputm_enabled && !is_vcpu_idle(vcpu))
                __start_cpu_timer_accounting(vcpu);
        vcpu->cpu = cpu;
}

void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
{
        vcpu->cpu = -1;
        if (vcpu->arch.cputm_enabled && !is_vcpu_idle(vcpu))
                __stop_cpu_timer_accounting(vcpu);
        atomic_andnot(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags);
        vcpu->arch.enabled_gmap = gmap_get_enabled();
        gmap_disable(vcpu->arch.enabled_gmap);

}

static void kvm_s390_vcpu_initial_reset(struct kvm_vcpu *vcpu)
{
        /* this equals initial cpu reset in pop, but we don't switch to ESA */
        vcpu->arch.sie_block->gpsw.mask = 0UL;
        vcpu->arch.sie_block->gpsw.addr = 0UL;
        kvm_s390_set_prefix(vcpu, 0);
        kvm_s390_set_cpu_timer(vcpu, 0);
        vcpu->arch.sie_block->ckc       = 0UL;
        vcpu->arch.sie_block->todpr     = 0;
        memset(vcpu->arch.sie_block->gcr, 0, 16 * sizeof(__u64));
        vcpu->arch.sie_block->gcr[0]  = 0xE0UL;
        vcpu->arch.sie_block->gcr[14] = 0xC2000000UL;
        /* make sure the new fpc will be lazily loaded */
        save_fpu_regs();
        current->thread.fpu.fpc = 0;
        vcpu->arch.sie_block->gbea = 1;
        vcpu->arch.sie_block->pp = 0;
        vcpu->arch.pfault_token = KVM_S390_PFAULT_TOKEN_INVALID;
        kvm_clear_async_pf_completion_queue(vcpu);
        if (!kvm_s390_user_cpu_state_ctrl(vcpu->kvm))
                kvm_s390_vcpu_stop(vcpu);
        kvm_s390_clear_local_irqs(vcpu);
}

void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
{
        mutex_lock(&vcpu->kvm->lock);
        preempt_disable();
        vcpu->arch.sie_block->epoch = vcpu->kvm->arch.epoch;
        preempt_enable();
        mutex_unlock(&vcpu->kvm->lock);
        if (!kvm_is_ucontrol(vcpu->kvm)) {
                vcpu->arch.gmap = vcpu->kvm->arch.gmap;
                sca_add_vcpu(vcpu);
        }
        if (test_kvm_facility(vcpu->kvm, 74) || vcpu->kvm->arch.user_instr0)
                vcpu->arch.sie_block->ictl |= ICTL_OPEREXC;
        /* make vcpu_load load the right gmap on the first trigger */
        vcpu->arch.enabled_gmap = vcpu->arch.gmap;
}

static void kvm_s390_vcpu_crypto_setup(struct kvm_vcpu *vcpu)
{
        if (!test_kvm_facility(vcpu->kvm, 76))
                return;

        vcpu->arch.sie_block->ecb3 &= ~(ECB3_AES | ECB3_DEA);

        if (vcpu->kvm->arch.crypto.aes_kw)
                vcpu->arch.sie_block->ecb3 |= ECB3_AES;
        if (vcpu->kvm->arch.crypto.dea_kw)
                vcpu->arch.sie_block->ecb3 |= ECB3_DEA;

        vcpu->arch.sie_block->crycbd = vcpu->kvm->arch.crypto.crycbd;
}

void kvm_s390_vcpu_unsetup_cmma(struct kvm_vcpu *vcpu)
{
        free_page(vcpu->arch.sie_block->cbrlo);
        vcpu->arch.sie_block->cbrlo = 0;
}

int kvm_s390_vcpu_setup_cmma(struct kvm_vcpu *vcpu)
{
        vcpu->arch.sie_block->cbrlo = get_zeroed_page(GFP_KERNEL);
        if (!vcpu->arch.sie_block->cbrlo)
                return -ENOMEM;

        vcpu->arch.sie_block->ecb2 &= ~ECB2_PFMFI;
        return 0;
}

static void kvm_s390_vcpu_setup_model(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_cpu_model *model = &vcpu->kvm->arch.model;

        vcpu->arch.sie_block->ibc = model->ibc;
        if (test_kvm_facility(vcpu->kvm, 7))
                vcpu->arch.sie_block->fac = (u32)(u64) model->fac_list;
}

int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
{
        int rc = 0;

        atomic_set(&vcpu->arch.sie_block->cpuflags, CPUSTAT_ZARCH |
                                                    CPUSTAT_SM |
                                                    CPUSTAT_STOPPED);

        if (test_kvm_facility(vcpu->kvm, 78))
                atomic_or(CPUSTAT_GED2, &vcpu->arch.sie_block->cpuflags);
        else if (test_kvm_facility(vcpu->kvm, 8))
                atomic_or(CPUSTAT_GED, &vcpu->arch.sie_block->cpuflags);

        kvm_s390_vcpu_setup_model(vcpu);

        /* pgste_set_pte has special handling for !MACHINE_HAS_ESOP */
        if (MACHINE_HAS_ESOP)
                vcpu->arch.sie_block->ecb |= ECB_HOSTPROTINT;
        if (test_kvm_facility(vcpu->kvm, 9))
                vcpu->arch.sie_block->ecb |= ECB_SRSI;
        if (test_kvm_facility(vcpu->kvm, 73))
                vcpu->arch.sie_block->ecb |= ECB_TE;

        if (test_kvm_facility(vcpu->kvm, 8) && sclp.has_pfmfi)
                vcpu->arch.sie_block->ecb2 |= ECB2_PFMFI;
        if (test_kvm_facility(vcpu->kvm, 130))
                vcpu->arch.sie_block->ecb2 |= ECB2_IEP;
        vcpu->arch.sie_block->eca = ECA_MVPGI | ECA_PROTEXCI;
        if (sclp.has_cei)
                vcpu->arch.sie_block->eca |= ECA_CEI;
        if (sclp.has_ib)
                vcpu->arch.sie_block->eca |= ECA_IB;
        if (sclp.has_siif)
                vcpu->arch.sie_block->eca |= ECA_SII;
        if (sclp.has_sigpif)
                vcpu->arch.sie_block->eca |= ECA_SIGPI;
        if (test_kvm_facility(vcpu->kvm, 129)) {
                vcpu->arch.sie_block->eca |= ECA_VX;
                vcpu->arch.sie_block->ecd |= ECD_HOSTREGMGMT;
        }
        if (test_kvm_facility(vcpu->kvm, 139))
                vcpu->arch.sie_block->ecd |= ECD_MEF;

        vcpu->arch.sie_block->sdnxo = ((unsigned long) &vcpu->run->s.regs.sdnx)
                                        | SDNXC;
        vcpu->arch.sie_block->riccbd = (unsigned long) &vcpu->run->s.regs.riccb;

        if (sclp.has_kss)
                atomic_or(CPUSTAT_KSS, &vcpu->arch.sie_block->cpuflags);
        else
                vcpu->arch.sie_block->ictl |= ICTL_ISKE | ICTL_SSKE | ICTL_RRBE;

        if (vcpu->kvm->arch.use_cmma) {
                rc = kvm_s390_vcpu_setup_cmma(vcpu);
                if (rc)
                        return rc;
        }
        hrtimer_init(&vcpu->arch.ckc_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
        vcpu->arch.ckc_timer.function = kvm_s390_idle_wakeup;

        kvm_s390_vcpu_crypto_setup(vcpu);

        return rc;
}

struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm,
                                      unsigned int id)
{
        struct kvm_vcpu *vcpu;
        struct sie_page *sie_page;
        int rc = -EINVAL;

        if (!kvm_is_ucontrol(kvm) && !sca_can_add_vcpu(kvm, id))
                goto out;

        rc = -ENOMEM;

        vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
        if (!vcpu)
                goto out;

        BUILD_BUG_ON(sizeof(struct sie_page) != 4096);
        sie_page = (struct sie_page *) get_zeroed_page(GFP_KERNEL);
        if (!sie_page)
                goto out_free_cpu;

        vcpu->arch.sie_block = &sie_page->sie_block;
        vcpu->arch.sie_block->itdba = (unsigned long) &sie_page->itdb;

        /* the real guest size will always be smaller than msl */
        vcpu->arch.sie_block->mso = 0;
        vcpu->arch.sie_block->msl = sclp.hamax;

        vcpu->arch.sie_block->icpua = id;
        spin_lock_init(&vcpu->arch.local_int.lock);
        vcpu->arch.local_int.float_int = &kvm->arch.float_int;
        vcpu->arch.local_int.wq = &vcpu->wq;
        vcpu->arch.local_int.cpuflags = &vcpu->arch.sie_block->cpuflags;
        seqcount_init(&vcpu->arch.cputm_seqcount);

        rc = kvm_vcpu_init(vcpu, kvm, id);
        if (rc)
                goto out_free_sie_block;
        VM_EVENT(kvm, 3, "create cpu %d at 0x%pK, sie block at 0x%pK", id, vcpu,
                 vcpu->arch.sie_block);
        trace_kvm_s390_create_vcpu(id, vcpu, vcpu->arch.sie_block);

        return vcpu;
out_free_sie_block:
        free_page((unsigned long)(vcpu->arch.sie_block));
out_free_cpu:
        kmem_cache_free(kvm_vcpu_cache, vcpu);
out:
        return ERR_PTR(rc);
}

int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
{
        return kvm_s390_vcpu_has_irq(vcpu, 0);
}

bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
{
        return !(vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE);
}

void kvm_s390_vcpu_block(struct kvm_vcpu *vcpu)
{
        atomic_or(PROG_BLOCK_SIE, &vcpu->arch.sie_block->prog20);
        exit_sie(vcpu);
}

void kvm_s390_vcpu_unblock(struct kvm_vcpu *vcpu)
{
        atomic_andnot(PROG_BLOCK_SIE, &vcpu->arch.sie_block->prog20);
}

static void kvm_s390_vcpu_request(struct kvm_vcpu *vcpu)
{
        atomic_or(PROG_REQUEST, &vcpu->arch.sie_block->prog20);
        exit_sie(vcpu);
}

static void kvm_s390_vcpu_request_handled(struct kvm_vcpu *vcpu)
{
        atomic_andnot(PROG_REQUEST, &vcpu->arch.sie_block->prog20);
}

/*
 * Kick a guest cpu out of SIE and wait until SIE is not running.
 * If the CPU is not running (e.g. waiting as idle) the function will
 * return immediately. */
void exit_sie(struct kvm_vcpu *vcpu)
{
        atomic_or(CPUSTAT_STOP_INT, &vcpu->arch.sie_block->cpuflags);
        while (vcpu->arch.sie_block->prog0c & PROG_IN_SIE)
                cpu_relax();
}

/* Kick a guest cpu out of SIE to process a request synchronously */
void kvm_s390_sync_request(int req, struct kvm_vcpu *vcpu)
{
        kvm_make_request(req, vcpu);
        kvm_s390_vcpu_request(vcpu);
}

static void kvm_gmap_notifier(struct gmap *gmap, unsigned long start,
                              unsigned long end)
{
        struct kvm *kvm = gmap->private;
        struct kvm_vcpu *vcpu;
        unsigned long prefix;
        int i;

        if (gmap_is_shadow(gmap))
                return;
        if (start >= 1UL << 31)
                /* We are only interested in prefix pages */
                return;
        kvm_for_each_vcpu(i, vcpu, kvm) {
                /* match against both prefix pages */
                prefix = kvm_s390_get_prefix(vcpu);
                if (prefix <= end && start <= prefix + 2*PAGE_SIZE - 1) {
                        VCPU_EVENT(vcpu, 2, "gmap notifier for %lx-%lx",
                                   start, end);
                        kvm_s390_sync_request(KVM_REQ_MMU_RELOAD, vcpu);
                }
        }
}

int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
{
        /* kvm common code refers to this, but never calls it */
        BUG();
        return 0;
}

static int kvm_arch_vcpu_ioctl_get_one_reg(struct kvm_vcpu *vcpu,
                                           struct kvm_one_reg *reg)
{
        int r = -EINVAL;

        switch (reg->id) {
        case KVM_REG_S390_TODPR:
                r = put_user(vcpu->arch.sie_block->todpr,
                             (u32 __user *)reg->addr);
                break;
        case KVM_REG_S390_EPOCHDIFF:
                r = put_user(vcpu->arch.sie_block->epoch,
                             (u64 __user *)reg->addr);
                break;
        case KVM_REG_S390_CPU_TIMER:
                r = put_user(kvm_s390_get_cpu_timer(vcpu),
                             (u64 __user *)reg->addr);
                break;
        case KVM_REG_S390_CLOCK_COMP:
                r = put_user(vcpu->arch.sie_block->ckc,
                             (u64 __user *)reg->addr);
                break;
        case KVM_REG_S390_PFTOKEN:
                r = put_user(vcpu->arch.pfault_token,
                             (u64 __user *)reg->addr);
                break;
        case KVM_REG_S390_PFCOMPARE:
                r = put_user(vcpu->arch.pfault_compare,
                             (u64 __user *)reg->addr);
                break;
        case KVM_REG_S390_PFSELECT:
                r = put_user(vcpu->arch.pfault_select,
                             (u64 __user *)reg->addr);
                break;
        case KVM_REG_S390_PP:
                r = put_user(vcpu->arch.sie_block->pp,
                             (u64 __user *)reg->addr);
                break;
        case KVM_REG_S390_GBEA:
                r = put_user(vcpu->arch.sie_block->gbea,
                             (u64 __user *)reg->addr);
                break;
        default:
                break;
        }

        return r;
}

static int kvm_arch_vcpu_ioctl_set_one_reg(struct kvm_vcpu *vcpu,
                                           struct kvm_one_reg *reg)
{
        int r = -EINVAL;
        __u64 val;

        switch (reg->id) {
        case KVM_REG_S390_TODPR:
                r = get_user(vcpu->arch.sie_block->todpr,
                             (u32 __user *)reg->addr);
                break;
        case KVM_REG_S390_EPOCHDIFF:
                r = get_user(vcpu->arch.sie_block->epoch,
                             (u64 __user *)reg->addr);
                break;
        case KVM_REG_S390_CPU_TIMER:
                r = get_user(val, (u64 __user *)reg->addr);
                if (!r)
                        kvm_s390_set_cpu_timer(vcpu, val);
                break;
        case KVM_REG_S390_CLOCK_COMP:
                r = get_user(vcpu->arch.sie_block->ckc,
                             (u64 __user *)reg->addr);
                break;
        case KVM_REG_S390_PFTOKEN:
                r = get_user(vcpu->arch.pfault_token,
                             (u64 __user *)reg->addr);
                if (vcpu->arch.pfault_token == KVM_S390_PFAULT_TOKEN_INVALID)
                        kvm_clear_async_pf_completion_queue(vcpu);
                break;
        case KVM_REG_S390_PFCOMPARE:
                r = get_user(vcpu->arch.pfault_compare,
                             (u64 __user *)reg->addr);
                break;
        case KVM_REG_S390_PFSELECT:
                r = get_user(vcpu->arch.pfault_select,
                             (u64 __user *)reg->addr);
                break;
        case KVM_REG_S390_PP:
                r = get_user(vcpu->arch.sie_block->pp,
                             (u64 __user *)reg->addr);
                break;
        case KVM_REG_S390_GBEA:
                r = get_user(vcpu->arch.sie_block->gbea,
                             (u64 __user *)reg->addr);
                break;
        default:
                break;
        }

        return r;
}

static int kvm_arch_vcpu_ioctl_initial_reset(struct kvm_vcpu *vcpu)
{
        kvm_s390_vcpu_initial_reset(vcpu);
        return 0;
}

int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
{
        memcpy(&vcpu->run->s.regs.gprs, &regs->gprs, sizeof(regs->gprs));
        return 0;
}

int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
{
        memcpy(&regs->gprs, &vcpu->run->s.regs.gprs, sizeof(regs->gprs));
        return 0;
}

int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
                                  struct kvm_sregs *sregs)
{
        memcpy(&vcpu->run->s.regs.acrs, &sregs->acrs, sizeof(sregs->acrs));
        memcpy(&vcpu->arch.sie_block->gcr, &sregs->crs, sizeof(sregs->crs));
        return 0;
}

int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
                                  struct kvm_sregs *sregs)
{
        memcpy(&sregs->acrs, &vcpu->run->s.regs.acrs, sizeof(sregs->acrs));
        memcpy(&sregs->crs, &vcpu->arch.sie_block->gcr, sizeof(sregs->crs));
        return 0;
}

int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
{
        if (test_fp_ctl(fpu->fpc))
                return -EINVAL;
        vcpu->run->s.regs.fpc = fpu->fpc;
        if (MACHINE_HAS_VX)
                convert_fp_to_vx((__vector128 *) vcpu->run->s.regs.vrs,
                                 (freg_t *) fpu->fprs);
        else
                memcpy(vcpu->run->s.regs.fprs, &fpu->fprs, sizeof(fpu->fprs));
        return 0;
}

int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
{
        /* make sure we have the latest values */
        save_fpu_regs();
        if (MACHINE_HAS_VX)
                convert_vx_to_fp((freg_t *) fpu->fprs,
                                 (__vector128 *) vcpu->run->s.regs.vrs);
        else
                memcpy(fpu->fprs, vcpu->run->s.regs.fprs, sizeof(fpu->fprs));
        fpu->fpc = vcpu->run->s.regs.fpc;
        return 0;
}

static int kvm_arch_vcpu_ioctl_set_initial_psw(struct kvm_vcpu *vcpu, psw_t psw)
{
        int rc = 0;

        if (!is_vcpu_stopped(vcpu))
                rc = -EBUSY;
        else {
                vcpu->run->psw_mask = psw.mask;
                vcpu->run->psw_addr = psw.addr;
        }
        return rc;
}

int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
                                  struct kvm_translation *tr)
{
        return -EINVAL; /* not implemented yet */
}

#define VALID_GUESTDBG_FLAGS (KVM_GUESTDBG_SINGLESTEP | \
                              KVM_GUESTDBG_USE_HW_BP | \
                              KVM_GUESTDBG_ENABLE)

int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
                                        struct kvm_guest_debug *dbg)
{
        int rc = 0;

        vcpu->guest_debug = 0;
        kvm_s390_clear_bp_data(vcpu);

        if (dbg->control & ~VALID_GUESTDBG_FLAGS)
                return -EINVAL;
        if (!sclp.has_gpere)
                return -EINVAL;

        if (dbg->control & KVM_GUESTDBG_ENABLE) {
                vcpu->guest_debug = dbg->control;
                /* enforce guest PER */
                atomic_or(CPUSTAT_P, &vcpu->arch.sie_block->cpuflags);

                if (dbg->control & KVM_GUESTDBG_USE_HW_BP)
                        rc = kvm_s390_import_bp_data(vcpu, dbg);
        } else {
                atomic_andnot(CPUSTAT_P, &vcpu->arch.sie_block->cpuflags);
                vcpu->arch.guestdbg.last_bp = 0;
        }

        if (rc) {
                vcpu->guest_debug = 0;
                kvm_s390_clear_bp_data(vcpu);
                atomic_andnot(CPUSTAT_P, &vcpu->arch.sie_block->cpuflags);
        }

        return rc;
}

int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
                                    struct kvm_mp_state *mp_state)
{
        /* CHECK_STOP and LOAD are not supported yet */
        return is_vcpu_stopped(vcpu) ? KVM_MP_STATE_STOPPED :
                                       KVM_MP_STATE_OPERATING;
}

int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
                                    struct kvm_mp_state *mp_state)
{
        int rc = 0;

        /* user space knows about this interface - let it control the state */
        vcpu->kvm->arch.user_cpu_state_ctrl = 1;

        switch (mp_state->mp_state) {
        case KVM_MP_STATE_STOPPED:
                kvm_s390_vcpu_stop(vcpu);
                break;
        case KVM_MP_STATE_OPERATING:
                kvm_s390_vcpu_start(vcpu);
                break;
        case KVM_MP_STATE_LOAD:
        case KVM_MP_STATE_CHECK_STOP:
                /* fall through - CHECK_STOP and LOAD are not supported yet */
        default:
                rc = -ENXIO;
        }

        return rc;
}

static bool ibs_enabled(struct kvm_vcpu *vcpu)
{
        return atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_IBS;
}

static int kvm_s390_handle_requests(struct kvm_vcpu *vcpu)
{
retry:
        kvm_s390_vcpu_request_handled(vcpu);
        if (!kvm_request_pending(vcpu))
                return 0;
        /*
         * We use MMU_RELOAD just to re-arm the ipte notifier for the
         * guest prefix page. gmap_mprotect_notify will wait on the ptl lock.
         * This ensures that the ipte instruction for this request has
         * already finished. We might race against a second unmapper that
         * wants to set the blocking bit. Lets just retry the request loop.
         */
        if (kvm_check_request(KVM_REQ_MMU_RELOAD, vcpu)) {
                int rc;
                rc = gmap_mprotect_notify(vcpu->arch.gmap,
                                          kvm_s390_get_prefix(vcpu),
                                          PAGE_SIZE * 2, PROT_WRITE);
                if (rc) {
                        kvm_make_request(KVM_REQ_MMU_RELOAD, vcpu);
                        return rc;
                }
                goto retry;
        }

        if (kvm_check_request(KVM_REQ_TLB_FLUSH, vcpu)) {
                vcpu->arch.sie_block->ihcpu = 0xffff;
                goto retry;
        }

        if (kvm_check_request(KVM_REQ_ENABLE_IBS, vcpu)) {
                if (!ibs_enabled(vcpu)) {
                        trace_kvm_s390_enable_disable_ibs(vcpu->vcpu_id, 1);
                        atomic_or(CPUSTAT_IBS,
                                        &vcpu->arch.sie_block->cpuflags);
                }
                goto retry;
        }

        if (kvm_check_request(KVM_REQ_DISABLE_IBS, vcpu)) {
                if (ibs_enabled(vcpu)) {
                        trace_kvm_s390_enable_disable_ibs(vcpu->vcpu_id, 0);
                        atomic_andnot(CPUSTAT_IBS,
                                          &vcpu->arch.sie_block->cpuflags);
                }
                goto retry;
        }

        if (kvm_check_request(KVM_REQ_ICPT_OPEREXC, vcpu)) {
                vcpu->arch.sie_block->ictl |= ICTL_OPEREXC;
                goto retry;
        }

        if (kvm_check_request(KVM_REQ_START_MIGRATION, vcpu)) {
                /*
                 * Disable CMMA virtualization; we will emulate the ESSA
                 * instruction manually, in order to provide additional
                 * functionalities needed for live migration.
                 */
                vcpu->arch.sie_block->ecb2 &= ~ECB2_CMMA;
                goto retry;
        }

        if (kvm_check_request(KVM_REQ_STOP_MIGRATION, vcpu)) {
                /*
                 * Re-enable CMMA virtualization if CMMA is available and
                 * was used.
                 */
                if ((vcpu->kvm->arch.use_cmma) &&
                    (vcpu->kvm->mm->context.use_cmma))
                        vcpu->arch.sie_block->ecb2 |= ECB2_CMMA;
                goto retry;
        }

        /* nothing to do, just clear the request */
        kvm_clear_request(KVM_REQ_UNHALT, vcpu);

        return 0;
}

void kvm_s390_set_tod_clock_ext(struct kvm *kvm,
                                 const struct kvm_s390_vm_tod_clock *gtod)
{
        struct kvm_vcpu *vcpu;
        struct kvm_s390_tod_clock_ext htod;
        int i;

        mutex_lock(&kvm->lock);
        preempt_disable();

        get_tod_clock_ext((char *)&htod);

        kvm->arch.epoch = gtod->tod - htod.tod;
        kvm->arch.epdx = gtod->epoch_idx - htod.epoch_idx;

        if (kvm->arch.epoch > gtod->tod)
                kvm->arch.epdx -= 1;

        kvm_s390_vcpu_block_all(kvm);
        kvm_for_each_vcpu(i, vcpu, kvm) {
                vcpu->arch.sie_block->epoch = kvm->arch.epoch;
                vcpu->arch.sie_block->epdx  = kvm->arch.epdx;
        }

        kvm_s390_vcpu_unblock_all(kvm);
        preempt_enable();
        mutex_unlock(&kvm->lock);
}

void kvm_s390_set_tod_clock(struct kvm *kvm, u64 tod)
{
        struct kvm_vcpu *vcpu;
        int i;

        mutex_lock(&kvm->lock);
        preempt_disable();
        kvm->arch.epoch = tod - get_tod_clock();
        kvm_s390_vcpu_block_all(kvm);
        kvm_for_each_vcpu(i, vcpu, kvm)
                vcpu->arch.sie_block->epoch = kvm->arch.epoch;
        kvm_s390_vcpu_unblock_all(kvm);
        preempt_enable();
        mutex_unlock(&kvm->lock);
}

/**
 * kvm_arch_fault_in_page - fault-in guest page if necessary
 * @vcpu: The corresponding virtual cpu
 * @gpa: Guest physical address
 * @writable: Whether the page should be writable or not
 *
 * Make sure that a guest page has been faulted-in on the host.
 *
 * Return: Zero on success, negative error code otherwise.
 */
long kvm_arch_fault_in_page(struct kvm_vcpu *vcpu, gpa_t gpa, int writable)
{
        return gmap_fault(vcpu->arch.gmap, gpa,